[ASP.NET]解決 GridView 匯出Excel 發生Control 'GridView1' of type 'GridView' must be placed inside a form tag with runat=server."

問題

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GridView 匯出Excel 發生Control 'GridView1' of type 'GridView' must be placed inside a form tag with runat=server."



解決方法

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語法如下:

protected void btnExportExcel_Click(object sender, EventArgs e)
{ 
 if (GridView1.Rows.Count > 0) 
 { 
  string attachment = string.Format("attachment; filename=allocationInvoice{0}.xls" , DateTime.Now.ToString(("yyyyMMddHHmmss"))); 
  Response.ClearContent(); 
  Response.AddHeader("content-disposition", attachment); 
  Response.ContentType = "application/ms-excel";
  StringWriter sw = new StringWriter(); 
  HtmlTextWriter htw = new HtmlTextWriter(sw);
  GridView1.RenderControl(htw); 
  Response.Write(sw.ToString()); 
  Response.End(); 
 } 
}

但是會發生錯誤下:
Control 'GridView1' of type 'GridView' must be placed inside a form tag with runat=server."
解決方式override 原有的function:

public override void VerifyRenderingInServerForm(Control control)
{
 
}