How to show related Data in Textbox using C#

Here I will show you how to Show Related Data In Textbox When We Click Related Item In Combobox In Csharp.

Create a table named employee having fileds empid Text, empname Text, sal Number , empaddress Text , phoneno Number in Ms-access.

Method 1:

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 Form1 : Form
{
string ConnectionString = System.Configuration.ConfigurationSettings.AppSettings["dsn"];
OleDbCommand com;
OleDbDataAdapter oledbda;
DataSet ds;
string str;
public Form1()
{
InitializeComponent();
}

private void Form1_Load(object sender, EventArgs e)
{

OleDbConnection con = new OleDbConnection(ConnectionString);
str = "select * from employee";
com = new OleDbCommand(str, con);
oledbda = new OleDbDataAdapter(com);
ds = new DataSet();
oledbda.Fill(ds, "employee");
comboBox1.DataSource = ds.Tables["employee"];
comboBox1.DisplayMember = "empid";
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();



}
}
}

Method 2:

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();

}
}
}

Method 3:

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 Form3 : Form
{
string ConnectionString = System.Configuration.ConfigurationSettings.AppSettings["dsn"];
OleDbCommand com;
OleDbDataAdapter oledbda;
DataSet ds;
string str;
DataTable dt;
public Form3()
{
InitializeComponent();
}

private void Form3_Load(object sender, EventArgs e)
{
OleDbConnection con = new OleDbConnection(ConnectionString);
con.Open();
str = "select * from employee";
com = new OleDbCommand(str, con);
oledbda = new OleDbDataAdapter(com);
ds = new DataSet();
oledbda.Fill(ds, "employee");
dt = ds.Tables["employee"];
int i;
for (i = 0; i <= dt.Rows.Count - 1; i++)
{
comboBox1.Items.Add(dt.Rows[i].ItemArray[0]);
}
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();
}
}
}

Running the program

After running the program when you select any empid from the combobox its corresponding values will be shown.



Thanks for reading.