How to remove duplicate records from a datatable?

protected void Button1_Click(object sender, EventArgs e)
{
string strConn = ConfigurationManager.ConnectionStrings["ConnectionString"].ToString();
SqlConnection conn = new SqlConnection(strConn);
SqlDataAdapter da = new SqlDataAdapter("select * from emp", conn);
DataSet ds = new DataSet();
da.Fill(ds, "Emp");
DataTable dt = ds.Tables["Emp"];
dt = RemoveDuplicateRows(dt, "empname");
GridView1.DataSource = ds.Tables["Emp"].DefaultView;
GridView1.DataBind();
}