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[操作系统]iOS之清除缓存


//清除缓存按钮的点击事件

- (void)putBufferBtnClicked:(UIButton *)btn{

     CGFloat size = [self folderSizeAtPath:NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES).lastObject] + [self folderSizeAtPath:NSSearchPathForDirectoriesInDomains(NSLibraryDirectory, NSUserDomainMask, YES).lastObject] + [self folderSizeAtPath:NSTemporaryDirectory()];

    

    NSString *message = size > 1 ? [NSString stringWithFormat:@"缓存%.2fM, 删除缓存", size] : [NSString stringWithFormat:@"缓存%.2fK, 删除缓存", size * 1024.0];

    

    UIAlertController *alert = [UIAlertController alertControllerWithTitle:nil message:message preferredStyle:(UIAlertControllerStyleAlert)];

    

    UIAlertAction *action = [UIAlertAction actionWithTitle:@"确定" style:(UIAlertActionStyleDefault) handler:^(UIAlertAction *action) {                [self cleanCaches];            }];

    

    UIAlertAction *cancel = [UIAlertAction actionWithTitle:@"取消" style:(UIAlertActionStyleCancel) handler:nil];

    [alert addAction:action];

    [alert addAction:cancel];

    [self showDetailViewController:alert sender:nil];

}

 

// 计算目录大小

- (CGFloat)folderSizeAtPath:(NSString *)path{

    // 利用NSFileManager实现对文件的管理

    NSFileManager *manager = [NSFileManager defaultManager];

    CGFloat size = 0;

    if ([manager fileExistsAtPath:path]) {

        // 获取该目录下的文件,计算其大小

        NSArray *childrenFile = [manager subpathsAtPath:path];

        for (NSString *fileName in childrenFile) {

            NSString *absolutePath = [path stringByAppendingPathComponent:fileName];

            size += [manager attributesOfItemAtPath:absolutePath error:nil].fileSize;

        }

        // 将大小转化为M

        return size / 1024.0 / 1024.0;

    }

    return 0;

}

// 根据路径删除文件

- (void)cleanCaches:(NSString *)path{

    // 利用NSFileManager实现对文件的管理

    NSFileManager *fileManager = [NSFileManager defaultManager];

    if ([fileManager fileExistsAtPath:path]) {

        // 获取该路径下面的文件名

        NSArray *childrenFiles = [fileManager subpathsAtPath:path];

        for (NSString *fileName in childrenFiles) {

            // 拼接路径

            NSString *absolutePath = [path stringByAppendingPathComponent:fileName];

            // 将文件删除

            [fileManager removeItemAtPath:absolutePath error:nil];

        }

    }

}

//计算沙盒中文件的大小并删除沙盒中文件的例子:

- (void)cleanCaches{

    [self cleanCaches:NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES).firstObject];

    [self cleanCaches:NSSearchPathForDirectoriesInDomains(NSLibraryDirectory, NSUserDomainMask, YES).firstObject];

    [self cleanCaches:NSTemporaryDirectory()];

}