comboBox_SelectedIndexChanged

Hi roi,

please refer this link
 http://www.c-sharpcorner.com/UploadFile/satyapriyanayak/8561/"









If this post help you please mark it as answer

hey vulpes... thank you for your help.

i'v tried your code but i get an error, thats my code: ("aptNum" is the primary key of Apartment table)

DataTable dt = (DataTable)comboBox4.DataSource;
int apartmentNum = (int)((DataRowView)comboBox4.SelectedItem)["aptNum"];
DataRow dr = dt.Rows.Find(apartmentNum);
textBox6.Text = dr["floor"].ToString();

i get the following error:

 Unable to cast object of type 'System.Windows.Forms.BindingSource' to type 'System.Data.DataTable'.

i'v tried to googel the error but nothing helpful came out, got any ideas?

Hi roi,

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Linq;

using System.Text;

using System.Windows.Forms;

using System.Data.OleDb;

namespace combobox_textbox_data

{

    public partial class Form2 : Form

    {

        string ConnectionString = System.Configuration.ConfigurationSettings.AppSettings["dsn"];

        OleDbCommand com;

        OleDbDataAdapter oledbda;

        DataSet ds;

        string str;

        public Form2()

        {

            InitializeComponent();

        }

 

        private void Form2_Load(object sender, EventArgs e)

        {

            OleDbConnection con = new OleDbConnection(ConnectionString);

            con.Open();

            str = "select * from employee";

            com = new OleDbCommand(str, con);

            OleDbDataReader reader = com.ExecuteReader();

            while (reader.Read())

            {

                comboBox1.Items.Add(reader["empid"]);

            }

            reader.Close();

            con.Close();

            comboBox1.Text = "select";

            textBox1.Text = "";

            textBox2.Text = "";

            textBox3.Text = "";

            textBox4.Text = "";

        }

 

        private void comboBox1_SelectedIndexChanged(object sender, EventArgs e)

        {

            OleDbConnection con = new OleDbConnection(ConnectionString);

            con.Open();

            str = "select * from employee where empid='" + comboBox1.Text.Trim() + "'";

            com = new OleDbCommand(str, con);

            OleDbDataReader reader = com.ExecuteReader();

 

            if (reader.Read())

            {

                textBox1.Text = reader["empname"].ToString();

                textBox2.Text = reader["sal"].ToString();

                textBox3.Text = reader["empaddress"].ToString();

                textBox4.Text = reader["phoneno"].ToString();

            }

 

            con.Close();

            reader.Close();

      

        }

    }

}

If this post help you please mark it as answer

// open you connection
  string SqlStr = "Select * From person where id=" + comboBox1.SelectedValue.ToString();
            SqlDataAdapter  da = new SqlDataAdapter (SqlStr, Your Sql Connection);
            DataTable dt = new DataTable();
            try
            {           
                da.Fill(dt);
            }
            catch
            {
                //Error
            }
            finally
            {
              close your connection
            }
//now fill the boxes
LabelFname.Text = dt.Rows[0]["FullName"].ToString();
LabelCity.Text = dt.Rows[0]["ProvinceName"].ToString();