/// <summary>
/// 构造函数，并指定图片格式处理器
/// </summary>
/// <param name="formatHandler">并指定图片格式处理器</param>
public MyScreenCapture(ImageFormatHandler formatHandler)
{
doc.PrintPage += new PrintPageEventHandler(printPage);
this.formatHandler = formatHandler;
}
/// <summary>
/// 构造函数
/// </summary>
public MyScreenCapture()
{
doc.PrintPage += new PrintPageEventHandler(printPage);
formatHandler = new ImageFormatHandler();
}