[asp.net-mvc] Export data to Excel file with ASP.NET MVC 4 C# is rendering into view

You can call helper class in any controller

//view 
 @Html.ActionLink("Export to Excel", "Excel")

//controller Action
public void Excel()
{
    var model = db.GetModel()

    Export export = new Export();
    export.ToExcel(Response, model);
}

//helper class
public class Export
{        public void ToExcel(HttpResponseBase Response, object clientsList)
    {
        var grid = new System.Web.UI.WebControls.GridView();
        grid.DataSource = clientsList;
        grid.DataBind();
        Response.ClearContent();
        Response.AddHeader("content-disposition", "attachment; filename=FileName.xls");
        Response.ContentType = "application/excel";
        StringWriter sw = new StringWriter();
        HtmlTextWriter htw = new HtmlTextWriter(sw);

        grid.RenderControl(htw);
        Response.Write(sw.ToString());
        Response.End();
    }
}