EndExecuteNonQuery Error

我有一个错误，这是在按钮单击事件，因为它显示了一个错误消息在这一行:

com.EndExecuteNonQuery ();

消息文本:错误2没有重载方法'EndExecuteNonQuery'接受0个参数

感谢您的支持

  protected void Page_Load(object sender, EventArgs e)
{
    if (IsPostBack)
    {
        SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["usradmadslistview"].ConnectionString);
        conn.Open();
        string cmdStr = "Select count(*) from UserInfo where UID = '" + UsrNme.Text + "'";
        SqlCommand com = new SqlCommand(cmdStr, conn);
        int temp = Convert.ToInt32(com.ExecuteScalar().ToString());

        if (temp == 1)
        {
            chkusrnamlbl.Visible = true;
        }
        conn.Close();
    }
}


protected void btnSave_Click(object sender, EventArgs e)
{
    try
    {
        SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["usradmadslistview"].ConnectionString);
        conn.Open();
        string insertquery = "insert into UserInfo (UID,FN,LN,Password,Email,CountID,State,City) Values (@username,@firstn,@lastn,@passbox,@email1,@country,@state,@city)";
        SqlCommand com = new SqlCommand(insertquery, conn);
        com.Parameters.AddWithValue("@username", UsrNme.Text);
        com.Parameters.AddWithValue("@firstn", fnbox.Text);
        com.Parameters.AddWithValue("@lastn", lnamebox.Text);
        com.Parameters.AddWithValue("@passbox", passtxtbx1.Text);
        com.Parameters.AddWithValue("@email1", emailbox.Text);
        com.Parameters.AddWithValue("@country", DrDncoundrlst.SelectedItem.ToString());
        com.Parameters.AddWithValue("@state", DropDownListSwestate.SelectedItem.ToString());
        com.Parameters.AddWithValue("@city", citytxtbox.Text);
        com.EndExecuteNonQuery();
        Response.Redirect("User panel.aspx");
        conn.Close();
    }
   catch(Exception ex) {
        Response.Write("Error:" + ex.ToString());
    }