C# CODES FOR VARIOUS DATABASE OPERATIONS

******SAVING THE RECORD******

SqlConnection cn = new SqlConnection
("Data Source=.\\SQLEXPRESS;AttachDbFilename=C:\\Users\\NAFEES\\Documents\\NIIST.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True");
            cn.Open();
            SqlCommand cmd=new SqlCommand("insert into emp values('"+textBox1.Text+"','"+textBox2.Text+"',"+textBox3.Text+")",cn);
                cmd.ExecuteNonQuery();
            MessageBox.Show("Records Entered Succesfully !");

******SEARCHING THE RECORD******

SqlConnection cn = new SqlConnection("Data Source=.\\SQLEXPRESS;AttachDbFilename=C:\\Users\\NAFEES\\Documents\\NIIST.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True");
            cn.Open();
            SqlCommand cmd = new SqlCommand("Select * from emp where ename='" + textBox1.Text + "'", cn);
            SqlDataReader dr = cmd.ExecuteReader();
            dr.Read();
            if(dr.HasRows)
            {
                label1.Text=dr["DESIG"].ToString();
                label2.Text = dr["SALARY"].ToString();
            }
            else
            {
                MessageBox.Show("Record Not Found");

******DELETING RECORD******

Int32 rowToDelete = this.dataGridView1.Rows.GetFirstRow(DataGridViewElementStates.Selected);
                   if (rowToDelete > -1)
                   {
                       this.dataGridView1.Rows.RemoveAt(rowToDelete);
                   }

****FUNCTION FOR DISPLAYING DATA IN DATA GRID****

void FillData()
    {
        // 1
        // Open connection
        SqlConnection cn = new SqlConnection("Data Source=.\\SQLEXPRESS;AttachDbFilename=C:\\Users\\NAFEES\\Documents\\NIIST.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True");
        cn.Open();
       
        // 2
        // Create new DataAdapter
        SqlDataAdapter a = new SqlDataAdapter(
            "SELECT * FROM emp", cn);
        {
            // 3
            // Use DataAdapter to fill DataTable
            DataTable t = new DataTable();
            a.Fill(t);
            // 4
            // Render data onto the screen
            dataGridView1.DataSource = t;
        }