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[ASP.net教程]ASP.NET控件之RadioButtonList


“RadioButtonList”控件表示一个封装了一组单选按钮控件的列表控件。

可以使用两种类型的 ASP.NET 控件将单选按钮添加到网页上:各个“RadioButton”控件或一个“RadioButtonList”控件。这两类控件都允许用户从一小组互相排斥的预定义选项中进行选择。使用这些控件,可定义任意数目的带标签的单选按钮,并将它们水平或垂直排列。

命名空间:System.Web.UI.WebControls
程序集:System.Web(在 system.web.dll 中)

[ValidationPropertyAttribute("SelectedItem")]
public class RadioButtonList : ListControl, IRepeatInfoUser, INamingContainer, IPostBackDataHandler
RadioButtonList 控件为网页开发人员提供了一组单选按钮,这些按钮可以通过数据绑定动态生成。该控件包含一个 Items 集合,集合中的成员与列表中的各项相对应。若要确定选择了哪一项,请测试列表的 SelectedItem 属性。

可以用 RepeatLayout 和 RepeatDirection 属性指定如何呈现列表。如果将 RepeatLayout 设置为 RepeatLayout.Table(默认设置),列表将呈现在表中。如果设置为 RepeatLayout.Flow,列表将不以表格形式呈现。默认情况下,RepeatDirection 设置为 RepeatDirection.Vertical。将该属性设置为 RepeatDirection.Horizontal 时,列表将水平呈现。

RadioButtonList用法

                <div >
                <asp:RadioButtonList ID="rblChangQHT" runat="server" RepeatDirection="Horizontal">
                <asp:ListItem Text="是" Value="1"></asp:ListItem>
                <asp:ListItem Text="否" Value="0"></asp:ListItem>
                </asp:RadioButtonList></div>

1.RadioButtonList 校验

            var rb_ChangQHT = document.getElementById("rblChangQHT");
            var ShiF = rb_ChangQHT.getElementsByTagName("INPUT");
            var result = false;
            for (var i = 0; i < ShiF.length; i++) {
                if (ShiF[i].checked) {
                    result = true;
                    break;
                }
            }
            if (!result) {
                alert("是否为中长期合同为必填项!");
                return false;
            }

2.RadioButtonList样式调整

.rblStyle{width:100%;height:auto;}
.rblStyle input{border-style:none;}

3.onselectedindexchanged事件

像下拉控件dropdownlist控件一样,它也有onselectedindexchanged事件,当选项改变后进行触发

注意点是:控件中的AutoPostBack属性一定设为"True",这样服务器端才知道你的选项改变了,并触发相应事件

4.为ListItem添加提示

            RadioButtonList1.Items[0].Attributes.Add("title", "提示内容");
5.绑定数据源

            string sql = "select * from province";
            DataTable dt = SQLHelper.ExecuteDataTable(sql);
            this.RadioButtonList1.DataSource = dt;
            this.RadioButtonList1.DataTextField = "Provinces";
            this.RadioButtonList1.DataValueField = "PId";
            this.RadioButtonList1.DataBind();
6.改变选中项的前景色

<asp:RadioButtonList ID="rblIsLock" runat="server" AutoPostBack="true" OnSelectedIndexChanged="rblIsLock_SelectedIndexChanged"  RepeatDirection="Horizontal" RepeatLayout="Flow">                        

<asp:ListItem Selected="True" Value="0">启用 </asp:ListItem>                        

<asp:ListItem Value="1">禁用 </asp:ListItem>

</asp:RadioButtonList>

<label>*禁用的用户将无法登录</label>

后台:  

protected void rblIsLock_SelectedIndexChanged(object sender, EventArgs e)    

{        

    var rbl = sender as RadioButtonList;        

    HighliehgSelectedItem(rbl);    

}

private void HighliehgSelectedItem(RadioButtonList rbl)    

{        

    foreach (ListItem li in rbl.Items)        

   {            

     if (li.Selected)            

    {         

       li.Attributes.Add("style", "color: red;");            

     }        

   }    

}

7.后台动态增加RadioButtonList

                    RadioButtonList rbl = new RadioButtonList();
                    rbl.ID = "rbl" + (i + 1).ToString();
                    rbl.BorderStyle = BorderStyle.None;
                    rbl.RepeatLayout = RepeatLayout.Flow;
                    rbl.RepeatDirection = RepeatDirection.Horizontal;
                    rbl.TextAlign = TextAlign.Right;
                    rbl.CellSpacing = 6;
                    rbl.Attributes.Add("onclick", "CheckRbl('ctl00_ctl00_ctl00_ContentPlaceHolder1_cphBody_cphLower_" + rbl.ID + "')");
                    rbl.DataSource = dtRating.DefaultView;
                    rbl.DataTextField = "LevelID";
                    rbl.DataValueField = "LevelID";
                    rbl.DataBind();
                    tc.Controls.Add(rbl); //tc是TableRow的一个单元格TableCell

                    for (int k = 0; k < rbl.Items.Count; k++)
                    {
                        rbl.Items[k].Attributes.Add("title", dtRating.Rows[k][1].ToString());
                        rbl.Items[k].Attributes.Add("style", "margin-left:10px;");
                    }

8.前台改变选中项的背景色

            window.onload = function () {
            var arr = document.getElementsByTagName("INPUT");
            for (var i = 0; i < arr.length; i++) {
                if (arr[i].checked) {
                    if (arr[i].type == "radio") {
                        arr[i].style.backgroundColor = "red";
                    }
                    else {
                        arr[i].style.backgroundColor = "";
                    }
                }
                else {
                    arr[i].style.backgroundColor = "";
                }
            }
        }