How to use Linkbutton control to download the document in ASP.NET?

My code so far…

protected void LinkButton3_Click(object sender, EventArgs e)
{
string filename = “~/Users/Kunal/Desktop/Website EasyGo Email/EasyMon Specifications_Rev1.1.pdf”;
if (filename != “”)
{
string path = Server.MapPath(filename);
System.IO.FileInfo file = new System.IO.FileInfo(path);
if (file.Exists)
{
Response.Clear();
Response.AddHeader(“Content-Disposition”, “attachment; filename=” +filename);
Response.AddHeader(“Content-Length”, file.Length.ToString());
Response.ContentType = “EasyMon Specifications_Rev1.1.pdf”;
Response.WriteFile(file.FullName);
Response.End();
}
else
{
Response.Write(“This file does not exist.”);
}
}

}