Editing records

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 Search_Edit { public partial class Form1 : Form { string ConnectionString = System.Configuration.ConfigurationSettings.AppSettings["dsn"]; OleDbCommand com; OleDbDataAdapter oledbda; string str; DataSet ds; public Form1() { InitializeComponent(); } private void btn_edit_Click(object sender, EventArgs e) { OleDbConnection con = new OleDbConnection(ConnectionString); con.Open(); str = "select * from student where id='"+ textBox1.Text+"'"; com = new OleDbCommand(str, con); OleDbDataReader reader = com.ExecuteReader(); while (reader.Read()) { textBox2.Text=(reader["name"].ToString()); textBox3.Text = (reader["mark"].ToString()); } reader.Close(); con.Close(); } private void btn_update_Click(object sender, EventArgs e) { OleDbConnection con = new OleDbConnection(ConnectionString); con.Open(); str = "update student set name='" + textBox2.Text + "',mark='" + textBox3.Text + "' where id='" + textBox1.Text + "'"; com = new OleDbCommand(str, con); com.ExecuteNonQuery(); con.Close(); MessageBox.Show("Records successfully updated"); } } }