将ASP.NET页面内容输出到字符串中

以下是一个页面code-behind的代码示例，其中利用了这个函数来对页面的输出内容进行过滤，经此处理后的内容才最终显示在浏览器中。

public partial class FilterDemo : System.Web.UI.Page

{

  HtmlTextWriter _oldWriter = null;

  StringWriter _stringWriter = new StringWriter();

  protected override HtmlTextWriter CreateHtmlTextWriter(TextWriter tw)

  {

    _oldWriter = base.CreateHtmlTextWriter(tw);

    return base.CreateHtmlTextWriter(_stringWriter);

  }

  protected override void Render(HtmlTextWriter writer)

  {

    base.Render(writer);

    string html = _stringWriter.ToString();

    html = html.Replace("REPLACE ME!", "IT WAS REPLACED!");

    _oldWriter.Write(html);

  }

}