逗号附加到gridview文本框

Question

我有一个gridview绑定到viewstate，viewstate拥有一个数据表。在gridview中，我有EditItemTemplates。

当我点击完成按钮时，modalpopup显示，

 protected void Button1_Click(object sender, System.EventArgs e)
 {
   mdlPopup.Show();
 }

protected void btnCancel_Click(object sender, EventArgs e)
{
    mdlPopup.Hide();       
}

每当发生回发时，gridview文本框中的数据会以附加的逗号重复。

我有Javascripts：

      <script type="text/javascript">
          //http://www.codingfusion.com/Post/Max-length-for-multiline-textbox-in-asp-net
          function Check(textBox, maxLength) {
              if (textBox.value.length > maxLength) {
                  alert("You cannot enter more than " + maxLength + " characters.");
                  textBox.value = textBox.value.substr(0, maxLength);
              }

          }

    </script>


    <script type="text/javascript">
        document.onkeydown = Esc;
        function Esc() {
            var KeyID = event.keyCode;
            if (KeyID == 27) {
                if ($find("mdlPopup")) {
                    $find("mdlPopup").hide();
                }
            }
        }
    </script>

Gridview转换为HTML代码：

 public override void VerifyRenderingInServerForm(Control control)
{
    /* Confirms that an HtmlForm control is rendered for the specified ASP.NET
       server control at run time. */
    return;
}
private string getHTML(GridView gv)
{
    StringBuilder sb = new StringBuilder();
    StringWriter textwriter = new StringWriter(sb);
    HtmlTextWriter htmlwriter = new HtmlTextWriter(textwriter);
    gv.RenderControl(htmlwriter);
    htmlwriter.Flush();
    textwriter.Flush();
    htmlwriter.Dispose();
    textwriter.Dispose();
    return sb.ToString();
}

我不知道逗号附加到文本框中文本的位置。

任何人都可以帮我这么做吗？ 提前谢谢。