protected void txtbox1_TextChanged(object sender, EventArgs e)
    {

        string str = "select TimeIn from MusterRoll where EmpCode='" + txtbox1.Text + "'";
        SqlDataReader dr=conn.query(str);
        if(dr.Read())
        {
            txtbox2.Text=dr[0].ToString();
        }
      }

textBox1.AutoPostBack = true;