ASP.NET - DataGrid Export to Excel - Alignment Problem

[genzy]

In the UI, the DataGrid width for each column have been defined,
but when it is exported to the Excel doc, alignment for each column is messed up in the Excel doc.

The problem is how to align the columns in Excel doc properly, exactly like the UI DataGrid columns.

Please advise.

HTML - Define the width of columns

 <asp:TemplateColumn HeaderText="No">
   <HeaderStyle Font-Bold="True" Width="1%"></HeaderStyle>
 ......
 <asp:TemplateColumn HeaderText="No">
    <HeaderStyle Font-Bold="True" Width="20%"></HeaderStyle>
 ......
 <asp:TemplateColumn HeaderText="No">
    <HeaderStyle Font-Bold="True" Width="20%"></HeaderStyle>
 ......
 ......

Code Behind - Export the whole DataGrid to the Excel doc.

   private void btnExportToDoc_Click(object sender, System.EventArgs e)
    {
    	string strTime = DateTime.Now.ToUniversalTime().ToString()+"_"+DateTime.Now.Millisecond.ToString();
    	strTime = strTime.Replace("/", "_");
    	strTime = strTime.Replace(":", "_");
    	strTime = strTime.Replace(" ", "_");
    	
    	Response.Clear();
    	Response.Buffer = true;
    	Response.AddHeader("content-disposition", "attachment; filename=FileDoc_"+strTime+".xls");
    	Response.ContentType = "application/vnd.ms-excel";
    	Response.Charset = "";
    	this.EnableViewState = false;
   	   
    	System.IO.StringWriter oStringWriter = new System.IO.StringWriter();
    	System.Web.UI.HtmlTextWriter oHtmlTextWriter = new System.Web.UI.HtmlTextWriter(oStringWriter);
    	
    	// Get the HTML for the control.
    	dgProdReleaseValid.RenderControl(oHtmlTextWriter);
    	// Write the HTML back to the browser.
    	Response.Write(oStringWriter.ToString());
  
    	Response.End();  
    }