How to export dynamically created table to excel? - asp.net

Question

In an aspx page:
<asp:table id = "table1" runat ="server"></table>
I have created a table using Javascript from the cs file like this:
StringBuilder sb = new StringBuilder()
sb.Append('<script>') ;
sb.Append(document.write('<table><tr><td>hghj</td></tr></table>'))
Table cell ;
Table row;
cell.Control.Add(new LiteralControl(sb.ToString())) ;
row.Control.Add(cell);
table1.Control.Add(row);
Now I want to export that table to excel, so I used the following code. It opened the excel file. But no data is seen.
Response.ContentType = "application/vnd.ms-excel";
Response.AddHeader("Content-Disposition", "attachment; filename=ExcelFile.xls");
Response.ContentEncoding = Encoding.UTF8;
StringWriter tw = new StringWriter();
HtmlTextWriter hw = new HtmlTextWriter(tw);
table1.RenderControl(hw);
Response.Write(tw.ToString());
Response.End();

Answer 1

I had a somewhat similar issue and the following solution worked for me. Hopefully it helps OP and others. In my case, the table data was dynamically being populated at run-time but when I tried to export the data to excel, I was getting a blank excel file. I solved this issue by putting my table generation code outside if (!IsPostBack){}. This is what my code structure looks like after that change:
protected void Page_Load(object sender, EventArgs e)
{
FunctionToPopulateTableDataAtRuntime();
if (!IsPostBack)
{
// other parts of the code
}
}
private void FunctionToPopulateTableDataAtRuntime()
{
// code to dynamically populate table data at run-time
// this code is somewhat similar to that of OP
// but it does not make use of JavaScript whatsoever
}
private void ExportTableToExcel()
{
// the code for this function is somewhat similar to what OP has
Response.ContentType = "application/vnd.ms-excel";
Response.AddHeader("Content-Disposition", "attachment; filename=test.xls;");
Response.ContentEncoding = Encoding.UTF8;
StringWriter stringWrite = new StringWriter();
HtmlTextWriter htmlWrite = new HtmlTextWriter(stringWrite);
myTable.RenderControl(htmlWrite);
Response.Write(stringWrite.ToString());
Response.End();
}
protected void btnExportToExcel_Click(object sender, EventArgs e)
{
ExportTableToExcel();
}
This is what the code-front (aspx) looks like:
<asp:Table
ID="myTable"
runat="server">
</asp:Table>
<asp:Button
ID="btnExportToExcel"
runat="server"
Text=" Export to Excel "
OnClick="btnExportToExcel_Click"/>

Answer 2

public override void VerifyRenderingInServerForm(Control control)
{
/* Verifies that the control is rendered */
}