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[ASP.net教程]Line Numbers for RichText Control in C#


from: http://www.codeproject.com/Articles/38858/Line-Numbers-for-RichText-Control-in-C

using Microsoft.VisualBasic;using System;using System.Collections;using System.Collections.Generic;using System.Data;using System.Drawing;using System.Drawing.Drawing2D;using System.Diagnostics;using System.Windows.Forms;namespace LineNumbers{  /// <summary>  /// http://www.codeproject.com/Articles/38858/Line-Numbers-for-RichText-Control-in-C  /// </summary>	[System.ComponentModel.DefaultProperty("ParentRichTextBox")]	public class LineNumbers_For_RichTextBox : System.Windows.Forms.Control	{		private class LineNumberItem		{			internal int LineNumber;			internal Rectangle Rectangle;			internal LineNumberItem(int zLineNumber, Rectangle zRectangle)			{				this.LineNumber = zLineNumber;				this.Rectangle = zRectangle;			}		}		public enum LineNumberDockSide : byte		{			None = 0,			Left = 1,			Right = 2,			Height = 4		}		private RichTextBox withEventsField_zParent = null;		private RichTextBox zParent {			get { return withEventsField_zParent; }			set {				if (withEventsField_zParent != null) {					withEventsField_zParent.LocationChanged -= zParent_Changed;					withEventsField_zParent.Move -= zParent_Changed;					withEventsField_zParent.Resize -= zParent_Changed;					withEventsField_zParent.DockChanged -= zParent_Changed;					withEventsField_zParent.TextChanged -= zParent_Changed;					withEventsField_zParent.MultilineChanged -= zParent_Changed;					withEventsField_zParent.HScroll -= zParent_Scroll;					withEventsField_zParent.VScroll -= zParent_Scroll;					withEventsField_zParent.ContentsResized -= zParent_ContentsResized;					withEventsField_zParent.Disposed -= zParent_Disposed;				}				withEventsField_zParent = value;				if (withEventsField_zParent != null) {					withEventsField_zParent.LocationChanged += zParent_Changed;					withEventsField_zParent.Move += zParent_Changed;					withEventsField_zParent.Resize += zParent_Changed;					withEventsField_zParent.DockChanged += zParent_Changed;					withEventsField_zParent.TextChanged += zParent_Changed;					withEventsField_zParent.MultilineChanged += zParent_Changed;					withEventsField_zParent.HScroll += zParent_Scroll;					withEventsField_zParent.VScroll += zParent_Scroll;					withEventsField_zParent.ContentsResized += zParent_ContentsResized;					withEventsField_zParent.Disposed += zParent_Disposed;				}			}		}				//private Windows.Forms.Timer withEventsField_zTimer = new Windows.Forms.Timer();		//private Windows.Forms.Timer zTimer {		//private Timer withEventsField_zTimer = new Windows.Forms.Timer();		private Timer withEventsField_zTimer = new Timer();		private Timer zTimer		{			get { return withEventsField_zTimer; }			set {				if (withEventsField_zTimer != null) {					withEventsField_zTimer.Tick -= zTimer_Tick;				}				withEventsField_zTimer = value;				if (withEventsField_zTimer != null) {					withEventsField_zTimer.Tick += zTimer_Tick;				}			}		}		private bool zAutoSizing = true;		private Size zAutoSizing_Size = new Size(0, 0);		//private Rectangle zContentRectangle = null;		private Rectangle zContentRectangle;		private LineNumberDockSide zDockSide = LineNumberDockSide.Left;		private bool zParentIsScrolling = false;		private bool zSeeThroughMode = false;		private bool zGradient_Show = true;		private System.Drawing.Drawing2D.LinearGradientMode zGradient_Direction = System.Drawing.Drawing2D.LinearGradientMode.Horizontal;		private Color zGradient_StartColor = Color.FromArgb(0, 0, 0, 0);		private Color zGradient_EndColor = Color.LightSteelBlue;		private bool zGridLines_Show = true;		private float zGridLines_Thickness = 1;		private System.Drawing.Drawing2D.DashStyle zGridLines_Style = System.Drawing.Drawing2D.DashStyle.Dot;		private Color zGridLines_Color = Color.SlateGray;		private bool zBorderLines_Show = true;		private float zBorderLines_Thickness = 1;		private System.Drawing.Drawing2D.DashStyle zBorderLines_Style = System.Drawing.Drawing2D.DashStyle.Dot;		private Color zBorderLines_Color = Color.SlateGray;		private bool zMarginLines_Show = true;		private LineNumberDockSide zMarginLines_Side = LineNumberDockSide.Right;		private float zMarginLines_Thickness = 1;		private System.Drawing.Drawing2D.DashStyle zMarginLines_Style = System.Drawing.Drawing2D.DashStyle.Solid;		private Color zMarginLines_Color = Color.SlateGray;		private bool zLineNumbers_Show = true;		private bool zLineNumbers_ShowLeadingZeroes = true;		private bool zLineNumbers_ShowAsHexadecimal = false;		private bool zLineNumbers_ClipByItemRectangle = true;		private Size zLineNumbers_Offset = new Size(0, 0);		private string zLineNumbers_Format = "0";		private System.Drawing.ContentAlignment zLineNumbers_Alignment = ContentAlignment.TopRight;				private bool zLineNumbers_AntiAlias = true;		private List<LineNumberItem> zLNIs = new List<LineNumberItem>();		private Point zPointInParent = new Point(0, 0);		private Point zPointInMe = new Point(0, 0);		private int zParentInMe = 0;		////////////////////////////////////////////////////////////////////////////////////////////////////		public LineNumbers_For_RichTextBox()		{			{				this.SetStyle(ControlStyles.OptimizedDoubleBuffer, true);				this.SetStyle(ControlStyles.ResizeRedraw, true);				this.SetStyle(ControlStyles.SupportsTransparentBackColor, true);				this.SetStyle(ControlStyles.UserPaint, true);				this.SetStyle(ControlStyles.AllPaintingInWmPaint, true);				this.Margin = new Padding(0);				this.Padding = new Padding(0, 0, 2, 0);			}			{				zTimer.Enabled = true;				zTimer.Interval = 200;				zTimer.Stop();			}			this.Update_SizeAndPosition();			this.Invalidate();		}		protected override void OnHandleCreated(System.EventArgs e)		{			base.OnHandleCreated(e);			this.AutoSize = false;		}		////////////////////////////////////////////////////////////////////////////////////////////////////		[System.ComponentModel.Browsable(false)]		public override bool AutoSize {			get { return base.AutoSize; }			set {				base.AutoSize = value;				this.Invalidate();			}		}		[System.ComponentModel.Description("Use this property to automatically resize the control (and reposition it if needed).")]		[System.ComponentModel.Category("Additional Behavior")]		public bool AutoSizing {			get { return zAutoSizing; }			set {				zAutoSizing = value;				this.Refresh();				this.Invalidate();			}		}		[System.ComponentModel.Description("Use this property to enable LineNumbers for the chosen RichTextBox.")]		[System.ComponentModel.Category("Add LineNumbers to")]		public RichTextBox ParentRichTextBox {			get { return zParent; }			set {				zParent = value;				if (zParent != null) {					this.Parent = zParent.Parent;					zParent.Refresh();				}				this.Text = "";				this.Refresh();				this.Invalidate();			}		}		[System.ComponentModel.Description("Use this property to dock the LineNumbers to a chosen side of the chosen RichTextBox.")]		[System.ComponentModel.Category("Additional Behavior")]		public LineNumberDockSide DockSide {			get { return zDockSide; }			set {				zDockSide = value;				this.Refresh();				this.Invalidate();			}		}		[System.ComponentModel.Description("Use this property to enable the control to act as an overlay ontop of the RichTextBox.")]		[System.ComponentModel.Category("Additional Behavior")]		public bool _SeeThroughMode_ {			get { return zSeeThroughMode; }			set {				zSeeThroughMode = value;				this.Invalidate();			}		}		[System.ComponentModel.Description("BorderLines are shown on all sides of the LineNumber control.")]		[System.ComponentModel.Category("Additional Behavior")]		public bool Show_BorderLines {			get { return zBorderLines_Show; }			set {				zBorderLines_Show = value;				this.Invalidate();			}		}		[System.ComponentModel.Category("Additional Appearance")]		public Color BorderLines_Color {			get { return zBorderLines_Color; }			set {				zBorderLines_Color = value;				this.Invalidate();			}		}		[System.ComponentModel.Category("Additional Appearance")]		public float BorderLines_Thickness {			get { return zBorderLines_Thickness; }			set {				zBorderLines_Thickness = Math.Max(1, Math.Min(255, value));				this.Invalidate();			}		}		[System.ComponentModel.Category("Additional Appearance")]		public System.Drawing.Drawing2D.DashStyle BorderLines_Style		{			get { return zBorderLines_Style; }			set {				if (value == System.Drawing.Drawing2D.DashStyle.Custom)					value = System.Drawing.Drawing2D.DashStyle.Solid;				zBorderLines_Style = value;				this.Invalidate();			}		}		[System.ComponentModel.Description("GridLines are the horizontal divider-lines shown above each LineNumber.")]		[System.ComponentModel.Category("Additional Behavior")]		public bool Show_GridLines {			get { return zGridLines_Show; }			set {				zGridLines_Show = value;				this.Invalidate();			}		}		[System.ComponentModel.Category("Additional Appearance")]		public Color GridLines_Color {			get { return zGridLines_Color; }			set {				zGridLines_Color = value;				this.Invalidate();			}		}		[System.ComponentModel.Category("Additional Appearance")]		public float GridLines_Thickness {			get { return zGridLines_Thickness; }			set {				zGridLines_Thickness = Math.Max(1, Math.Min(255, value));				this.Invalidate();			}		}		[System.ComponentModel.Category("Additional Appearance")]		public System.Drawing.Drawing2D.DashStyle GridLines_Style		{			get { return zGridLines_Style; }			set {				if (value == System.Drawing.Drawing2D.DashStyle.Custom)					value = System.Drawing.Drawing2D.DashStyle.Solid;				zGridLines_Style = value;				this.Invalidate();			}		}		[System.ComponentModel.Description("MarginLines are shown on the Left or Right (or both in Height-mode) of the LineNumber control.")]		[System.ComponentModel.Category("Additional Behavior")]		public bool Show_MarginLines {			get { return zMarginLines_Show; }			set {				zMarginLines_Show = value;				this.Invalidate();			}		}		[System.ComponentModel.Category("Additional Appearance")]		public LineNumberDockSide MarginLines_Side {			get { return zMarginLines_Side; }			set {				zMarginLines_Side = value;				this.Invalidate();			}		}		[System.ComponentModel.Category("Additional Appearance")]		public Color MarginLines_Color {			get { return zMarginLines_Color; }			set {				zMarginLines_Color = value;				this.Invalidate();			}		}		[System.ComponentModel.Category("Additional Appearance")]		public float MarginLines_Thickness {			get { return zMarginLines_Thickness; }			set {				zMarginLines_Thickness = Math.Max(1, Math.Min(255, value));				this.Invalidate();			}		}		[System.ComponentModel.Category("Additional Appearance")]		public System.Drawing.Drawing2D.DashStyle MarginLines_Style		{			get { return zMarginLines_Style; }			set {				if (value == System.Drawing.Drawing2D.DashStyle.Custom)					value = System.Drawing.Drawing2D.DashStyle.Solid;				zMarginLines_Style = value;				this.Invalidate();			}		}		[System.ComponentModel.Description("The BackgroundGradient is a gradual blend of two colors, shown in the back of each LineNumber's item-area.")]		[System.ComponentModel.Category("Additional Behavior")]		public bool Show_BackgroundGradient {			get { return zGradient_Show; }			set {				zGradient_Show = value;				this.Invalidate();			}		}		[System.ComponentModel.Category("Additional Appearance")]		public Color BackgroundGradient_AlphaColor {			get { return zGradient_StartColor; }			set {				zGradient_StartColor = value;				this.Invalidate();			}		}		[System.ComponentModel.Category("Additional Appearance")]		public Color BackgroundGradient_BetaColor {			get { return zGradient_EndColor; }			set {				zGradient_EndColor = value;				this.Invalidate();			}		}		[System.ComponentModel.Category("Additional Appearance")]		public System.Drawing.Drawing2D.LinearGradientMode BackgroundGradient_Direction		{			get { return zGradient_Direction; }			set {				zGradient_Direction = value;				this.Invalidate();			}		}		[System.ComponentModel.Category("Additional Behavior")]		public bool Show_LineNrs {			get { return zLineNumbers_Show; }			set {				zLineNumbers_Show = value;				this.Invalidate();			}		}		[System.ComponentModel.Description("Use this to set whether the LineNumbers are allowed to spill out of their item-area, or should be clipped by it.")]		[System.ComponentModel.Category("Additional Behavior")]		public bool LineNrs_ClippedByItemRectangle {			get { return zLineNumbers_ClipByItemRectangle; }			set {				zLineNumbers_ClipByItemRectangle = value;				this.Invalidate();			}		}		[System.ComponentModel.Description("Use this to set whether the LineNumbers should have leading zeroes (based on the total amount of textlines).")]		[System.ComponentModel.Category("Additional Behavior")]		public bool LineNrs_LeadingZeroes {			get { return zLineNumbers_ShowLeadingZeroes; }			set {				zLineNumbers_ShowLeadingZeroes = value;				this.Refresh();				this.Invalidate();			}		}		[System.ComponentModel.Description("Use this to set whether the LineNumbers should be shown as hexadecimal values.")]		[System.ComponentModel.Category("Additional Behavior")]		public bool LineNrs_AsHexadecimal {			get { return zLineNumbers_ShowAsHexadecimal; }			set {				zLineNumbers_ShowAsHexadecimal = value;				this.Refresh();				this.Invalidate();			}		}		[System.ComponentModel.Description("Use this property to manually reposition the LineNumbers, relative to their current location.")]		[System.ComponentModel.Category("Additional Behavior")]		public Size LineNrs_Offset {			get { return zLineNumbers_Offset; }			set {				zLineNumbers_Offset = value;				this.Invalidate();			}		}		[System.ComponentModel.Description("Use this to align the LineNumbers to a chosen corner (or center) within their item-area.")]		[System.ComponentModel.Category("Additional Behavior")]		public System.Drawing.ContentAlignment LineNrs_Alignment {			get { return zLineNumbers_Alignment; }			set {				zLineNumbers_Alignment = value;				this.Invalidate();			}		}		[System.ComponentModel.Description("Use this to apply Anti-Aliasing to the LineNumbers (high quality). Some fonts will look better without it, though.")]		[System.ComponentModel.Category("Additional Behavior")]		public bool LineNrs_AntiAlias {			get { return zLineNumbers_AntiAlias; }			set {				zLineNumbers_AntiAlias = value;				this.Refresh();				this.Invalidate();			}		}		[System.ComponentModel.Browsable(true)]		public override System.Drawing.Font Font {			get { return base.Font; }			set {				base.Font = value;				this.Refresh();				this.Invalidate();			}		}		[System.ComponentModel.DefaultValue("")]		[System.ComponentModel.AmbientValue("")]		[System.ComponentModel.Browsable(false)]		public override string Text {			get { return base.Text; }			set {				base.Text = "";				this.Invalidate();			}		}		////////////////////////////////////////////////////////////////////////////////////////////////////		protected override void OnSizeChanged(System.EventArgs e)		{			if (this.DesignMode == true)				this.Refresh();			base.OnSizeChanged(e);			this.Invalidate();		}		protected override void OnLocationChanged(System.EventArgs e)		{			if (this.DesignMode == true)				this.Refresh();			base.OnLocationChanged(e);			this.Invalidate();		}		public override void Refresh()		{			//  Note: don't change the order here, first the Mybase.Refresh, then the Update_SizeAndPosition.			base.Refresh();			this.Update_SizeAndPosition();		}		/// <summary>		/// This Sub will run whenever Me.Refresh() is called. It applies the AutoSizing and DockSide settings.		/// </summary>		/// <remarks></remarks>		private void Update_SizeAndPosition()		{			if (this.AutoSize == true)				return;			if (this.Dock == DockStyle.Bottom | this.Dock == DockStyle.Fill | this.Dock == DockStyle.Top)				return;			Point zNewLocation = this.Location;			Size zNewSize = this.Size;			if (zAutoSizing == true) {				//switch (true) {				//	case zParent == null:				if (zParent == null ){						// --- ReminderMessage sizing						if (zAutoSizing_Size.Width > 0)							zNewSize.Width = zAutoSizing_Size.Width;						if (zAutoSizing_Size.Height > 0)							zNewSize.Height = zAutoSizing_Size.Height;						this.Size = zNewSize;						// break;				}else if (this.Dock == DockStyle.Left | this.Dock == DockStyle.Right){					//--- zParent isNot Nothing for the following cases					//case this.Dock == DockStyle.Left | this.Dock == DockStyle.Right:						if (zAutoSizing_Size.Width > 0)							zNewSize.Width = zAutoSizing_Size.Width;						this.Width = zNewSize.Width;						//break;				}else if (zDockSide != LineNumberDockSide.None){					// --- DockSide is active L/R/H					//case zDockSide != LineNumberDockSide.None:						if (zAutoSizing_Size.Width > 0)							zNewSize.Width = zAutoSizing_Size.Width;						zNewSize.Height = zParent.Height;						if (zDockSide == LineNumberDockSide.Left)							zNewLocation.X = zParent.Left - zNewSize.Width - 1;						if (zDockSide == LineNumberDockSide.Right)							zNewLocation.X = zParent.Right + 1;						zNewLocation.Y = zParent.Top;						this.Location = zNewLocation;						this.Size = zNewSize;						//break;				} else if (zDockSide == LineNumberDockSide.None) {					// --- DockSide = None, but AutoSizing is still setting the Width					//case zDockSide == LineNumberDockSide.None:						if (zAutoSizing_Size.Width > 0)							zNewSize.Width = zAutoSizing_Size.Width;						this.Size = zNewSize;						//break;				}			} else {				// --- No AutoSizing				//switch (true) {				if (zParent == null){					//case zParent == null:						// --- ReminderMessage sizing						if (zAutoSizing_Size.Width > 0)							zNewSize.Width = zAutoSizing_Size.Width;						if (zAutoSizing_Size.Height > 0)							zNewSize.Height = zAutoSizing_Size.Height;						this.Size = zNewSize;						//break;				}else if (zDockSide != LineNumberDockSide.None){					// --- No AutoSizing, but DockSide L/R/H is active so height and position need updates.					//case zDockSide != LineNumberDockSide.None:						zNewSize.Height = zParent.Height;						if (zDockSide == LineNumberDockSide.Left)							zNewLocation.X = zParent.Left - zNewSize.Width - 1;						if (zDockSide == LineNumberDockSide.Right)							zNewLocation.X = zParent.Right + 1;						zNewLocation.Y = zParent.Top;						this.Location = zNewLocation;						this.Size = zNewSize;						//break;				}			}		}		/// <summary>		/// This Sub determines which textlines are visible in the ParentRichTextBox, and makes LineNumberItems (LineNumber + ItemRectangle)		/// for each visible line. They are put into the zLNIs List that will be used by the OnPaint event to draw the LineNumberItems. 		/// </summary>		/// <remarks></remarks>		private void Update_VisibleLineNumberItems()		{			// ################			int tmpY;			// ###############			zLNIs.Clear();			zAutoSizing_Size = new Size(0, 0);			zLineNumbers_Format = "0";			//initial setting			//  To measure the LineNumber's width, its Format 0 is replaced by w as that is likely to be one of the widest characters in non-monospace fonts. 			if (zAutoSizing == true)				zAutoSizing_Size = new Size(TextRenderer.MeasureText(zLineNumbers_Format.Replace('0', 'W'), this.Font).Width, 0);				//zAutoSizing_Size = new Size(TextRenderer.MeasureText(zLineNumbers_Format.Replace("0".ToCharArray(), "W".ToCharArray()), this.Font).Width, 0);			if (zParent == null || string.IsNullOrEmpty(zParent.Text))				return;			// --- Make sure the LineNumbers are aligning to the same height as the zParent textlines by converting to screencoordinates			//  and using that as an offset that gets added to the points for the LineNumberItems			zPointInParent = zParent.PointToScreen(zParent.ClientRectangle.Location);			zPointInMe = this.PointToScreen(new Point(0, 0));			//  zParentInMe is the vertical offset to make the LineNumberItems line up with the textlines in zParent.			zParentInMe = zPointInParent.Y - zPointInMe.Y + 1;			//  The first visible LineNumber may not be the first visible line of text in the RTB if the LineNumbercontrol's .Top is lower on the form than			//  the .Top of the parent RichTextBox. Therefor, zPointInParent will now be used to find zPointInMe's equivalent height in zParent, 			//  which is needed to find the best StartIndex later on.			zPointInParent = zParent.PointToClient(zPointInMe);			// --- NOTES: 			//  Additional complication is the fact that when wordwrap is enabled on the RTB, the wordwrapped text spills into the RTB.Lines collection, 			//  so we need to split the text into lines ourselves, and use the Index of each zSplit-line's first character instead of the RTB's.			string[] zSplit = zParent.Text.Split(Constants.vbCrLf.ToCharArray());			if (zSplit.Length < 2) {				//  Just one line in the text = one linenumber				//  NOTE: zContentRectangle is built by the zParent.ContentsResized event.				Point zPoint = zParent.GetPositionFromCharIndex(0);				zLNIs.Add(new LineNumberItem(1, new Rectangle(new Point(0, zPoint.Y - 1 + zParentInMe), new Size(this.Width, zContentRectangle.Height - zPoint.Y))));			} else {				//  Multiple lines, but store only those LineNumberItems for lines that are visible.				TimeSpan zTimeSpan = new TimeSpan(DateAndTime.Now.Ticks);				Point zPoint = new Point(0, 0);				int zStartIndex = 0;				int zSplitStartLine = 0;				int zA = zParent.Text.Length - 1;				// #########################										//this.FindStartIndex(ref zStartIndex, ref zA, ref zPointInParent.Y);					tmpY = zPointInParent.Y;					this.FindStartIndex(ref zStartIndex, ref zA, ref tmpY);					zPointInParent.Y = tmpY;				// ################				//  zStartIndex now holds the index of a character in the first visible line from zParent.Text				//  Now it will be pointed at the first character of that line (chr(10) = Linefeed part of the vbCrLf constant)				zStartIndex = Math.Max(0, Math.Min(zParent.Text.Length - 1, zParent.Text.Substring(0, zStartIndex).LastIndexOf(Strings.Chr(10)) + 1));				//  We now need to find out which zSplit-line that character is in, by counting the vbCrlf appearances that come before it.				zSplitStartLine = Math.Max(0, zParent.Text.Substring(0, zStartIndex).Split(Constants.vbCrLf.ToCharArray()).Length - 1);				//  zStartIndex starts off pointing at the first character of the first visible line, and will be then be pointed to 				//  the index of the first character on the next line.				for (zA = zSplitStartLine; zA <= zSplit.Length - 1; zA++) {					zPoint = zParent.GetPositionFromCharIndex(zStartIndex);					zStartIndex += Math.Max(1, zSplit[zA].Length + 1);					if (zPoint.Y + zParentInMe > this.Height)						break; // TODO: might not be correct. Was : Exit For					//  For performance reasons, the list of LineNumberItems (zLNIs) is first built with only the location of its 					//  itemrectangle being used. The height of those rectangles will be computed afterwards by comparing the items' Y coordinates.					zLNIs.Add(new LineNumberItem(zA + 1, new Rectangle(0, zPoint.Y - 1 + zParentInMe, this.Width, 1)));					if (zParentIsScrolling == true && DateAndTime.Now.Ticks > zTimeSpan.Ticks + 500000) {						//  The more lines there are in the RTB, the slower the RTB's .GetPositionFromCharIndex() method becomes						//  To avoid those delays from interfering with the scrollingspeed, this speedbased exit for is applied (0.05 sec)						//  zLNIs will have at least 1 item, and if that's the only one, then change its location to 0,0 to make it readable						if (zLNIs.Count == 1)							zLNIs[0].Rectangle.Y = 0;							// zLNIs(0).Rectangle.Y = 0;						zParentIsScrolling = false;						zTimer.Start();						break; // TODO: might not be correct. Was : Exit For					}				}				if (zLNIs.Count == 0)					return;				//  Add an extra placeholder item to the end, to make the heightcomputation easier				if (zA < zSplit.Length) {					//  getting here means the for/next loop was exited before reaching the last zSplit textline					//  zStartIndex will still be pointing to the startcharacter of the next line, so we can use that:					zPoint = zParent.GetPositionFromCharIndex(Math.Min(zStartIndex, zParent.Text.Length - 1));					zLNIs.Add(new LineNumberItem(-1, new Rectangle(0, zPoint.Y - 1 + zParentInMe, 0, 0)));				} else {					//  getting here means the for/next loop ran to the end (zA is now zSplit.Length). 					zLNIs.Add(new LineNumberItem(-1, new Rectangle(0, zContentRectangle.Bottom, 0, 0)));				}				//  And now we can easily compute the height of the LineNumberItems by comparing each item's Y coordinate with that of the next line.				//  There's at least two items in the list, and the last item is a "nextline-placeholder" that will be removed.				for (zA = 0; zA <= zLNIs.Count - 2; zA++) {					zLNIs[zA].Rectangle.Height = Math.Max(1, zLNIs[zA + 1].Rectangle.Y - zLNIs[zA].Rectangle.Y);					//zLNIs(zA).Rectangle.Height = Math.Max(1, zLNIs(zA + 1).Rectangle.Y - zLNIs(zA).Rectangle.Y);				}				//  Removing the placeholder item				zLNIs.RemoveAt(zLNIs.Count - 1);				// Set the Format to the width of the highest possible number so that LeadingZeroes shows the correct amount of zeroes.				if (zLineNumbers_ShowAsHexadecimal == true) {					//zLineNumbers_Format = "".PadRight(zSplit.Length.ToString("X").Length, "0");					zLineNumbers_Format = "".PadRight(zSplit.Length.ToString("X").Length, '0');				} else {					//zLineNumbers_Format = "".PadRight(zSplit.Length.ToString().Length, "0");					zLineNumbers_Format = "".PadRight(zSplit.Length.ToString().Length, '0');				}			}			//  To measure the LineNumber's width, its Format 0 is replaced by w as that is likely to be one of the widest characters in non-monospace fonts. 			if (zAutoSizing == true)				zAutoSizing_Size = new Size(TextRenderer.MeasureText(zLineNumbers_Format.Replace('0', 'W'), this.Font).Width, 0);				//zAutoSizing_Size = new Size(TextRenderer.MeasureText(zLineNumbers_Format.Replace("0".ToCharArray(), "W".ToCharArray()), this.Font).Width, 0);		}		/// <summary>		/// FindStartIndex is a recursive Sub (one that calls itself) to compute the first visible line that should have a LineNumber.		/// </summary>		/// <param name="zMin"> this will hold the eventual BestStartIndex when the Sub has completed its run.</param>		/// <param name="zMax"></param>		/// <param name="zTarget"></param>		/// <remarks></remarks>		private void FindStartIndex(ref int zMin, ref int zMax, ref int zTarget)		{			//  Recursive Sub to compute best starting index - only run when zParent is known to exist			if (zMax == zMin + 1 | zMin == (zMax + zMin) / 2)				return;			if(zParent.GetPositionFromCharIndex((zMax + zMin) / 2).Y == zTarget){				//switch (zParent.GetPositionFromCharIndex((zMax + zMin) / 2).Y) {				//	case // ERROR: Case labels with binary operators are unsupported : Equality				//  BestStartIndex found				zMin = (zMax + zMin) / 2;				//break;			}			else if (zParent.GetPositionFromCharIndex((zMax + zMin) / 2).Y > zTarget)			{				//case // ERROR: Case labels with binary operators are unsupported : GreaterThan				//zTarget:				//  Look again, in lower half				zMax = (zMax + zMin) / 2;				FindStartIndex(ref zMin, ref zMax, ref zTarget);				//break;			}			else if (zParent.GetPositionFromCharIndex((zMax + zMin) / 2).Y < 0)			{				// case // ERROR: Case labels with binary operators are unsupported : LessThan				//0:				//  Look again, in top half				zMin = (zMax + zMin) / 2;				FindStartIndex(ref zMin, ref zMax, ref zTarget);				//break;			}		}		/// <summary>		/// OnPaint will go through the enabled elements (vertical ReminderMessage, GridLines, LineNumbers, BorderLines, MarginLines) and will		/// draw them if enabled. At the same time, it will build GraphicsPaths for each of those elements (that are enabled), which will be used 		/// in SeeThroughMode (if it's active): the figures in the GraphicsPaths will form a customized outline for the control by setting them as the 		/// Region of the LineNumber control. Note: the vertical ReminderMessages are only drawn during designtime. 		/// </summary>		/// <param name="e"></param>		/// <remarks></remarks>		protected override void OnPaint(System.Windows.Forms.PaintEventArgs e)		{			//  Build the list of visible LineNumberItems (= zLNIs) first. (doesn't take long, so it can stay in OnPaint)			this.Update_VisibleLineNumberItems();			base.OnPaint(e);			// --- QualitySettings			if (zLineNumbers_AntiAlias == true) {				e.Graphics.TextRenderingHint = System.Drawing.Text.TextRenderingHint.AntiAlias;			} else {				e.Graphics.TextRenderingHint = System.Drawing.Text.TextRenderingHint.SystemDefault;			}			// --- Local Declarations			string zTextToShow = "";			string zReminderToShow = "";			StringFormat zSF = new StringFormat();			SizeF zTextSize = default(SizeF);			Pen zPen = new Pen(this.ForeColor);			SolidBrush zBrush = new SolidBrush(this.ForeColor);			Point zPoint = new Point(0, 0);			Rectangle zItemClipRectangle = new Rectangle(0, 0, 0, 0);			//  NOTE: The GraphicsPaths are only used for SeeThroughMode			//  FillMode.Winding: combined outline ( Alternate: XOR'ed outline )			System.Drawing.Drawing2D.GraphicsPath zGP_GridLines = new System.Drawing.Drawing2D.GraphicsPath(System.Drawing.Drawing2D.FillMode.Winding);			System.Drawing.Drawing2D.GraphicsPath zGP_BorderLines = new System.Drawing.Drawing2D.GraphicsPath(System.Drawing.Drawing2D.FillMode.Winding);			System.Drawing.Drawing2D.GraphicsPath zGP_MarginLines = new System.Drawing.Drawing2D.GraphicsPath(System.Drawing.Drawing2D.FillMode.Winding);			System.Drawing.Drawing2D.GraphicsPath zGP_LineNumbers = new System.Drawing.Drawing2D.GraphicsPath(System.Drawing.Drawing2D.FillMode.Winding);			Region zRegion = new Region(base.ClientRectangle);			// ----------------------------------------------			// --- DESIGNTIME / NO VISIBLE ITEMS			if (this.DesignMode == true) {				//  Show a vertical reminder message				if (zParent == null) {					zReminderToShow = "-!- Set ParentRichTextBox -!-";				} else {					if (zLNIs.Count == 0)						zReminderToShow = "LineNrs ( " + zParent.Name + " )";				}				if (zReminderToShow.Length > 0) {					// --- Centering and Rotation for the reminder message					e.Graphics.TranslateTransform(this.Width / 2, this.Height / 2);					e.Graphics.RotateTransform(-90);					zSF.Alignment = StringAlignment.Center;					zSF.LineAlignment = StringAlignment.Center;					// --- Show the reminder message (with small shadow)					zTextSize = e.Graphics.MeasureString(zReminderToShow, this.Font, zPoint, zSF);					e.Graphics.DrawString(zReminderToShow, this.Font, Brushes.WhiteSmoke, 1, 1, zSF);					e.Graphics.DrawString(zReminderToShow, this.Font, Brushes.Firebrick, 0, 0, zSF);					e.Graphics.ResetTransform();					//Rectangle zReminderRectangle = new Rectangle(this.Width / 2 - zTextSize.Height / 2, this.Height / 2 - zTextSize.Width / 2, zTextSize.Height, zTextSize.Width);					Rectangle zReminderRectangle = new Rectangle((int)(this.Width / 2 - zTextSize.Height / 2), (int)(this.Height / 2 - zTextSize.Width / 2), (int)(zTextSize.Height), (int)(zTextSize.Width));					zGP_LineNumbers.AddRectangle(zReminderRectangle);					zGP_LineNumbers.CloseFigure();					if (zAutoSizing == true) {						zReminderRectangle.Inflate((int)(zTextSize.Height * 0.2), (int)(zTextSize.Width * 0.1));						//zReminderRectangle.Inflate(zTextSize.Height * 0.2, zTextSize.Width * 0.1);						zAutoSizing_Size = new Size(zReminderRectangle.Width, zReminderRectangle.Height);					}				}			}			// ----------------------------------------------			// --- DESIGN OR RUNTIME / WITH VISIBLE ITEMS (which means zParent exists)			if (zLNIs.Count > 0) {				//  The visible LineNumberItems with their BackgroundGradient and GridLines				//  Loop through every visible LineNumberItem				System.Drawing.Drawing2D.LinearGradientBrush zLGB = null;				zPen = new Pen(zGridLines_Color, zGridLines_Thickness);				zPen.DashStyle = zGridLines_Style;				zSF.Alignment = StringAlignment.Near;				zSF.LineAlignment = StringAlignment.Near;				//zSF.FormatFlags = StringFormatFlags.FitBlackBox + StringFormatFlags.NoClip + StringFormatFlags.NoWrap;				zSF.FormatFlags = StringFormatFlags.FitBlackBox | StringFormatFlags.NoClip | StringFormatFlags.NoWrap;				for (int zA = 0; zA <= zLNIs.Count - 1; zA++) {					// --- BackgroundGradient					if (zGradient_Show == true) {						//zLGB = new Drawing2D.LinearGradientBrush(zLNIs(zA).Rectangle, zGradient_StartColor, zGradient_EndColor, zGradient_Direction);						zLGB = new System.Drawing.Drawing2D.LinearGradientBrush(zLNIs[zA].Rectangle, zGradient_StartColor, zGradient_EndColor, zGradient_Direction);						e.Graphics.FillRectangle(zLGB, zLNIs[zA].Rectangle);						//e.Graphics.FillRectangle(zLGB, zLNIs(zA).Rectangle);					}					// --- GridLines					if (zGridLines_Show == true) {						e.Graphics.DrawLine(zPen, new Point(0, zLNIs[zA].Rectangle.Y), new Point(this.Width, zLNIs[zA].Rectangle.Y));						//e.Graphics.DrawLine(zPen, new Point(0, zLNIs(zA).Rectangle.Y), new Point(this.Width, zLNIs(zA).Rectangle.Y));						//  NOTE: Every item in a GraphicsPath is a closed figure, so instead of adding gridlines as lines, we'll add them						//  as rectangles that loop out of sight. Their height uses the zContentRectangle which is the maxsize of 						//  the ParentRichTextBox's contents. 						//  NOTE: Slight adjustment needed when the first item has a negative Y coordinate. 						//  This explains the " - zLNIs(0).Rectangle.Y" (which adds the negative size to the height 						//  to make sure the rectangle's bottompart stays out of sight) 						//zGP_GridLines.AddRectangle(new Rectangle(-zGridLines_Thickness, zLNIs(zA).Rectangle.Y, this.Width + zGridLines_Thickness * 2, this.Height - zLNIs(0).Rectangle.Y + zGridLines_Thickness));						zGP_GridLines.AddRectangle(new Rectangle(	(int)(-zGridLines_Thickness),																											(int)(zLNIs[zA].Rectangle.Y),																											(int)(this.Width + zGridLines_Thickness * 2),																											(int)(this.Height - zLNIs[zA].Rectangle.Y + zGridLines_Thickness)																											));						zGP_GridLines.CloseFigure();					}					// --- LineNumbers					if (zLineNumbers_Show == true) {						//  TextFormatting						if (zLineNumbers_ShowLeadingZeroes == true) {							zTextToShow = (zLineNumbers_ShowAsHexadecimal ? zLNIs[zA].LineNumber.ToString("X") : zLNIs[zA].LineNumber.ToString(zLineNumbers_Format));							//zTextToShow = (zLineNumbers_ShowAsHexadecimal ? zLNIs(zA).LineNumber.ToString("X") : zLNIs(zA).LineNumber.ToString(zLineNumbers_Format));						} else {							zTextToShow = (zLineNumbers_ShowAsHexadecimal ? zLNIs[zA].LineNumber.ToString("X") : zLNIs[zA].LineNumber.ToString());							//zTextToShow = (zLineNumbers_ShowAsHexadecimal ? zLNIs(zA).LineNumber.ToString("X") : zLNIs(zA).LineNumber.ToString);						}						//  TextSizing						zTextSize = e.Graphics.MeasureString(zTextToShow, this.Font, zPoint, zSF);						//  TextAlignment and positioning  (zPoint = TopLeftCornerPoint of the text)						//  TextAlignment, padding, manual offset (via LineNrs_Offset) and zTextSize are all included in the calculation of zPoint. 						switch (zLineNumbers_Alignment) {							case ContentAlignment.TopLeft:								zPoint = new Point((int)(zLNIs[zA].Rectangle.Left + this.Padding.Left + zLineNumbers_Offset.Width), (int)(zLNIs[zA].Rectangle.Top + this.Padding.Top + zLineNumbers_Offset.Height));								break;							case ContentAlignment.MiddleLeft:								zPoint = new Point((int)(zLNIs[zA].Rectangle.Left + this.Padding.Left + zLineNumbers_Offset.Width), (int)(zLNIs[zA].Rectangle.Top + (zLNIs[zA].Rectangle.Height / 2) + zLineNumbers_Offset.Height - zTextSize.Height / 2));								break;							case ContentAlignment.BottomLeft:								zPoint = new Point((int)(zLNIs[zA].Rectangle.Left + this.Padding.Left + zLineNumbers_Offset.Width), (int)(zLNIs[zA].Rectangle.Bottom - this.Padding.Bottom + 1 + zLineNumbers_Offset.Height - zTextSize.Height));								break;							case ContentAlignment.TopCenter:								zPoint = new Point((int)(zLNIs[zA].Rectangle.Width / 2 + zLineNumbers_Offset.Width - zTextSize.Width / 2), (int)(zLNIs[zA].Rectangle.Top + this.Padding.Top + zLineNumbers_Offset.Height));								break;							case ContentAlignment.MiddleCenter:								zPoint = new Point((int)(zLNIs[zA].Rectangle.Width / 2 + zLineNumbers_Offset.Width - zTextSize.Width / 2), (int)(zLNIs[zA].Rectangle.Top + (zLNIs[zA].Rectangle.Height / 2) + zLineNumbers_Offset.Height - zTextSize.Height / 2));								break;							case ContentAlignment.BottomCenter:								zPoint = new Point((int)(zLNIs[zA].Rectangle.Width / 2 + zLineNumbers_Offset.Width - zTextSize.Width / 2), (int)(zLNIs[zA].Rectangle.Bottom - this.Padding.Bottom + 1 + zLineNumbers_Offset.Height - zTextSize.Height));								break;							case ContentAlignment.TopRight:								zPoint = new Point((int)(zLNIs[zA].Rectangle.Right - this.Padding.Right + zLineNumbers_Offset.Width - zTextSize.Width), (int)(zLNIs[zA].Rectangle.Top + this.Padding.Top + zLineNumbers_Offset.Height));								break;							case ContentAlignment.MiddleRight:								zPoint = new Point((int)(zLNIs[zA].Rectangle.Right - this.Padding.Right + zLineNumbers_Offset.Width - zTextSize.Width), (int)(zLNIs[zA].Rectangle.Top + (zLNIs[zA].Rectangle.Height / 2) + zLineNumbers_Offset.Height - zTextSize.Height / 2));								break;							case ContentAlignment.BottomRight:								zPoint = new Point((int)(zLNIs[zA].Rectangle.Right - this.Padding.Right + zLineNumbers_Offset.Width - zTextSize.Width), (int)(zLNIs[zA].Rectangle.Bottom - this.Padding.Bottom + 1 + zLineNumbers_Offset.Height - zTextSize.Height));								break;						}						//  TextClipping						zItemClipRectangle = new Rectangle(zPoint, zTextSize.ToSize());						if (zLineNumbers_ClipByItemRectangle == true) {							//  If selected, the text will be clipped so that it doesn't spill out of its own LineNumberItem-area.							//  Only the part of the text inside the LineNumberItem.Rectangle should be visible, so intersect with the ItemRectangle							//  The SetClip method temporary restricts the drawing area of the control for whatever is drawn next.							zItemClipRectangle.Intersect(zLNIs[zA].Rectangle);							e.Graphics.SetClip(zItemClipRectangle);						}						//  TextDrawing						e.Graphics.DrawString(zTextToShow, this.Font, zBrush, zPoint, zSF);						e.Graphics.ResetClip();						//  The GraphicsPath for the LineNumber is just a rectangle behind the text, to keep the paintingspeed high and avoid ugly artifacts.						zGP_LineNumbers.AddRectangle(zItemClipRectangle);						zGP_LineNumbers.CloseFigure();					}				}				// --- GridLinesThickness and Linestyle in SeeThroughMode. All GraphicsPath lines are drawn as solid to keep the paintingspeed high.				if (zGridLines_Show == true) {					zPen.DashStyle = System.Drawing.Drawing2D.DashStyle.Solid;					zGP_GridLines.Widen(zPen);				}				// --- Memory CleanUp				if (zLGB != null)					zLGB.Dispose();			}			// ----------------------------------------------			// --- DESIGN OR RUNTIME / ALWAYS			//Point zP_Left = new Point(Math.Floor(zBorderLines_Thickness / 2), Math.Floor(zBorderLines_Thickness / 2));			//Point zP_Right = new Point(this.Width - Math.Ceiling(zBorderLines_Thickness / 2), this.Height - Math.Ceiling(zBorderLines_Thickness / 2));			Point zP_Left = new Point(																	(int)(Math.Floor(zBorderLines_Thickness / 2)),																	(int)(Math.Floor(zBorderLines_Thickness / 2))															 );			Point zP_Right = new Point(																	(int)(this.Width - Math.Ceiling(zBorderLines_Thickness / 2)),																	(int)(this.Height - Math.Ceiling(zBorderLines_Thickness / 2))																);			// --- BorderLines 			Point[] zBorderLines_Points = {				new Point(zP_Left.X, zP_Left.Y),				new Point(zP_Right.X, zP_Left.Y),				new Point(zP_Right.X, zP_Right.Y),				new Point(zP_Left.X, zP_Right.Y),				new Point(zP_Left.X, zP_Left.Y)			};			if (zBorderLines_Show == true) {				zPen = new Pen(zBorderLines_Color, zBorderLines_Thickness);				zPen.DashStyle = zBorderLines_Style;				e.Graphics.DrawLines(zPen, zBorderLines_Points);				zGP_BorderLines.AddLines(zBorderLines_Points);				zGP_BorderLines.CloseFigure();				//  BorderThickness and Style for SeeThroughMode				zPen.DashStyle = System.Drawing.Drawing2D.DashStyle.Solid;				zGP_BorderLines.Widen(zPen);			}			// --- MarginLines 			if (zMarginLines_Show == true && zMarginLines_Side > LineNumberDockSide.None) {				zP_Left = new Point((int)(-zMarginLines_Thickness), (int)(-zMarginLines_Thickness));				zP_Right = new Point((int)(this.Width + zMarginLines_Thickness), (int)(this.Height + zMarginLines_Thickness));				zPen = new Pen(zMarginLines_Color, zMarginLines_Thickness);				zPen.DashStyle = zMarginLines_Style;				if (zMarginLines_Side == LineNumberDockSide.Left | zMarginLines_Side == LineNumberDockSide.Height) {					e.Graphics.DrawLine(zPen, new Point(																							(int)(Math.Floor(zMarginLines_Thickness / 2)), 0),																							new Point(																												(int)(Math.Floor(zMarginLines_Thickness / 2)),																												this.Height - 1)																												);					zP_Left = new Point(															(int)(Math.Ceiling(zMarginLines_Thickness / 2)),															(int)(-zMarginLines_Thickness));				}				if (zMarginLines_Side == LineNumberDockSide.Right | zMarginLines_Side == LineNumberDockSide.Height) {					e.Graphics.DrawLine(zPen, new Point(																							(int)(this.Width - Math.Ceiling(zMarginLines_Thickness / 2)), 0),																							new Point(																												(int)(this.Width - Math.Ceiling(zMarginLines_Thickness / 2)),																												(int)(this.Height - 1))																						);					zP_Right = new Point(																(int)(this.Width - Math.Ceiling(zMarginLines_Thickness / 2)),																(int)(this.Height + zMarginLines_Thickness)															);				}				//  GraphicsPath for the MarginLines(s):				//  MarginLines(s) are drawn as a rectangle connecting the zP_Left and zP_Right points, which are either inside or 				//  outside of sight, depending on whether the MarginLines at that side is visible. zP_Left: TopLeft and ZP_Right: BottomRight				zGP_MarginLines.AddRectangle(new Rectangle(zP_Left, new Size(zP_Right.X - zP_Left.X, zP_Right.Y - zP_Left.Y)));				zPen.DashStyle = System.Drawing.Drawing2D.DashStyle.Solid;				zGP_MarginLines.Widen(zPen);			}			// ----------------------------------------------			// --- SeeThroughMode			//  combine all the GraphicsPaths (= zGP_... ) and set them as the region for the control.			if (zSeeThroughMode == true) {				zRegion.MakeEmpty();				zRegion.Union(zGP_BorderLines);				zRegion.Union(zGP_MarginLines);				zRegion.Union(zGP_GridLines);				zRegion.Union(zGP_LineNumbers);			}			// --- Region			if (zRegion.GetBounds(e.Graphics).IsEmpty == true) {				//  Note: If the control is in a condition that would show it as empty, then a border-region is still drawn regardless of it's borders on/off state.				//  This is added to make sure that the bounds of the control are never lost (it would remain empty if this was not done).				zGP_BorderLines.AddLines(zBorderLines_Points);				zGP_BorderLines.CloseFigure();				zPen = new Pen(zBorderLines_Color, 1);				zPen.DashStyle = System.Drawing.Drawing2D.DashStyle.Solid;				zGP_BorderLines.Widen(zPen);				zRegion = new Region(zGP_BorderLines);			}			this.Region = zRegion;			// ----------------------------------------------			// --- Memory CleanUp			if (zPen != null)				zPen.Dispose();			if (zBrush != null)				zPen.Dispose();			if (zRegion != null)				zRegion.Dispose();			if (zGP_GridLines != null)				zGP_GridLines.Dispose();			if (zGP_BorderLines != null)				zGP_BorderLines.Dispose();			if (zGP_MarginLines != null)				zGP_MarginLines.Dispose();			if (zGP_LineNumbers != null)				zGP_LineNumbers.Dispose();		}		////////////////////////////////////////////////////////////////////////////////////////////////////		private void zTimer_Tick(object sender, System.EventArgs e)		{			zParentIsScrolling = false;			zTimer.Stop();			this.Invalidate();		}		private void zParent_Changed(object sender, System.EventArgs e)		{			this.Refresh();			this.Invalidate();		}		private void zParent_Scroll(object sender, System.EventArgs e)		{			zParentIsScrolling = true;			this.Invalidate();		}		private void zParent_ContentsResized(object sender, System.Windows.Forms.ContentsResizedEventArgs e)		{			zContentRectangle = e.NewRectangle;			this.Refresh();			this.Invalidate();		}		private void zParent_Disposed(object sender, System.EventArgs e)		{			this.ParentRichTextBox = null;			this.Refresh();			this.Invalidate();		}	}}