Get the ID of the selected value from a combobox

Question

    private void frmNSS5_Load(object sender, System.EventArgs e)
    {
        SqlConnection con;
        SqlCommand cmd;
        SqlDataReader dr;
        con = new SqlConnection(@"workstation id = PC-PC; user id=sa;Password=sapassword; data source=pc-pc; persist security info=True; initial catalog=CleanPayrollTest2");
        cmd = new SqlCommand("SELECT IsNull(ArEmpName,'') + ' ' + IsNull(ArFatherName,'') + ' ' + IsNull(ArLastName,'') as EmpName, ID as ID FROM [Emp] ", con);
        try
        {
            con.Open();
            dr = cmd.ExecuteReader();
            DataSet ds = new DataSet();
            DataTable dt = new DataTable();
            this.cbEmpName.ValueMember = "ID".ToString();
            this.cbEmpName.DisplayMember = "EmpName";
            this.cbEmpName.DataSource = ds.Tables["EmpName"];
            while (dr.Read())
            {
                if(dr[0].ToString().Length > 0)
                {
                    this.cbEmpName.Items.Add(dr[0].ToString());
                }
            }
        con.Close();
        }
        catch
        {
            MessageBox.Show("Connection Failed");
        }

}
    private void comboEmpName_SelectedIndexChanged(object sender, System.EventArgs e)
    {

        MessageBox.Show("Emp ID:" + ' ' + this.cbEmpName.SelectedValue + ", " + "EmpName:" + ' ' + this.cbEmpName.SelectedItem   );
    }

I'm not getting the ID while selecting an employee, the messssage box just show me the name... Can someone tell me where's my fault? Thank you so much

Answer 1

After databinding the combobox you delete the binding by inserting the values using a datareader. Just remove this part:

while (dr.Read())
{
    if(dr[0].ToString().Length > 0)
    {
        this.cbEmpName.Items.Add(dr[0].ToString());
    }
}

If you want to keep the code you should change the line that adds the item so it includes both the Value and the display data:

this.cbEmpName.Items.Add(
    new { EmpName = dr[0].ToString(), ID = dr[1].ToString()});

Answer 2

尝试这个

this.cbEmpName.Items.Add(new ListItem(dr[0].ToString(),dr[4].ToString()));