title: How can I format a column from a GridView before export to show all numbers in excel?
body: <p>I'm trying to export a GridView to Excel and I have a column with a series of numbers like 1245333325364. When I run the query for the GridView I can see the complete number but when I export to excel all I see is 1.00133E+12 on that column. I know I can have the user change this in excel but not all files are being open after export they just save it straight into a directory. I will really like to change the column's format in the export process rather than having the user do it before they save the file. I'm performing the export in C# any help will be really appreciate.</p>
  
  <p>The code I'm using to export the GridView is like so:</p>
  
  <pre><code>    protected void exporttoexcel_Click(object sender, EventArgs e)
      {
          string date = DateTime.Now.ToString("MM-dd-yyyy");
  
          PrepareGridViewForExport(GridView1);
          Response.Clear();
          Response.Buffer = true;
  
          Response.AddHeader("content-disposition", "attachment;filename=" + date + "_" + CHROUT.Text + "_Trailer_" + TRAILER.Text);
          Response.Charset = "''";
          Response.ContentType = "application/vnd.ms-excel";
          StringWriter sw = new StringWriter();
          HtmlTextWriter hw = new HtmlTextWriter(sw);
  
          GridView1.AllowPaging = false;
          GridView1.DataBind();
  
          GridView1.HeaderRow.Style.Add("background-color", "#FFFFFF");
          GridView1.HeaderRow.Cells[0].Style.Add("width", "105px");
          GridView1.HeaderRow.Cells[0].Style.Add("background-color", "#CCCCCC");
          GridView1.HeaderRow.Cells[1].Style.Add("background-color", "#CCCCCC");
          GridView1.HeaderRow.Cells[2].Style.Add("background-color", "#CCCCCC");
          GridView1.HeaderRow.Cells[3].Style.Add("background-color", "#CCCCCC");
          GridView1.HeaderRow.Cells[4].Style.Add("background-color", "#CCCCCC");
          GridView1.HeaderRow.Cells[5].Style.Add("background-color", "#CCCCCC");
          GridView1.HeaderRow.Cells[6].Style.Add("background-color", "#CCCCCC");
          GridView1.HeaderRow.Cells[7].Style.Add("background-color", "#CCCCCC");
  
          for (int i = 0; i &lt; GridView1.Rows.Count; i++)
          {
              GridViewRow row = GridView1.Rows[i];
  
              row.BackColor = System.Drawing.Color.White;
  
              row.Attributes.Add("class", "texmode");
  
              if (i % 2 != 0)
              {
                  row.Cells[0].Style.Add("background-color", "#f0f0f0");
                  row.Cells[1].Style.Add("background-color", "#f0f0f0");
                  row.Cells[2].Style.Add("background-color", "#f0f0f0");
                  row.Cells[3].Style.Add("background-color", "#f0f0f0");
                  row.Cells[4].Style.Add("background-color", "#f0f0f0");
                  row.Cells[5].Style.Add("background-color", "#f0f0f0");
                  row.Cells[6].Style.Add("background-color", "#f0f0f0");
                  row.Cells[7].Style.Add("background-color", "#f0f0f0");
              }
          }
          GridView1.RenderControl(hw);
          //style to format numbers to string
          string style = @"&lt;style&gt; .text { mso-number-format:\@; } &lt;/style&gt;";
          Response.Write(style);
          Response.Output.Write(sw.ToString());
          Response.Flush();
          Response.End();
      }
  </code></pre>