Database Connectivity

 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.SqlClient;

namespace WindowsFormsApplication3

{

public partial class Form1 : Form

{

SqlConnection con = new SqlConnection(@"Data 

Source=.\SQLEXPRESS;AttachDbFilename=C:\Users\kisho\OneDrive\Documents\Empl

oyee.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True");

public Form1()

{

InitializeComponent();

}

private void Form1_Load(object sender, EventArgs e)

{

}

private void button2_Click(object sender, EventArgs e)

{

con.Open();

SqlCommand cmd = new SqlCommand ("Insert into Employee_Table 

values('"+textBox1.Text+"','"+textBox2.Text+"','"+textBox3.Text +"','"+textBox4 

.Text+"','"+comboBox1 .Text +"')",con);

cmd.ExecuteNonQuery();

MessageBox .Show("Insert data successfully");

con.Close();

}

private void button1_Click(object sender, EventArgs e)

{

textBox1.Text = textBox2.Text = textBox3.Text = textBox4.Text = "";

}

private void button3_Click(object sender, EventArgs e)

{

con.Open();

SqlCommand cmd = new SqlCommand ("update Employee_Table SET Employee_Name

= '"+textBox2.Text+"',Address = '"+textBox3 .Text +"', salary ='"+textBox4 .Text +"'

where Employee_Id='"+textBox1 .Text+"'",con);

cmd.ExecuteNonQuery();

MessageBox.Show("Update data successfully");

con.Close();

}

private void button4_Click(object sender, EventArgs e)

{

con.Open();

SqlCommand cmd = new SqlCommand("Delete Employee_Table where Employee_Id='"

+textBox1.Text + "'", con);

cmd.ExecuteNonQuery();

MessageBox.Show("Delete data successfully");

con.Close();

}

private void button5_Click(object sender, EventArgs e)

{

textBox1.Text = textBox2.Text = textBox3.Text = textBox4.Text = "";

}

}

}