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asp.nethtmlexcelexport-to-excel

Export to Excel from ASP.NET produces files unreadable with Excel Viewer

I want to output some dynamic data from an ASP.NET website to Excel. I found that the easiest way which does not require to use Excel XML or to install Excel on server machine is to output data as a table and specify application/vnd.ms-excel type.

The problem is when I do so and try to open the file in Excel Viewer, I receive the following error message:

Microsoft Excel Viewer cannot open files of this type.

Then nothing is opened.

Even an easiest code such as:

protected void Page_Load(object sender, EventArgs e)
{
    Response.Clear();
    Response.Buffer = true;
    HttpContext.Current.Response.AddHeader("content-disposition", "attachment; filename=Example.xls");
    Response.ContentType = "application/vnd.ms-excel";
    StringWriter stringWriter = new System.IO.StringWriter();
    HtmlTextWriter htmlTextWriter = new System.Web.UI.HtmlTextWriter(stringWriter);
    dataGrid.RenderControl(htmlTextWriter);
    Response.Write("<html><body><table><tr><td>A</td><td>B</td></tr><tr><td>C</td><td>D</td></tr></table></body></html>");
    Response.End();
}

produces the same error.

What can cause such behavior? Is it because the Viewer cannot read such files, but full Excel version can?

Solution

  • Excel reader can only open excel files. You really aren't exporting it as an excel file, you are exporting it as a csv or html. It's not the same.

    EDIT

    Have you tried this Export to Excel?