update query is not working in ASP.NET web application - asp.net

Question

using System.Data.SqlClient;
using System.Data.Sql;
public partial class _Default : System.Web.UI.Page
{
SqlConnection con = new SqlConnection(#"Data Source=GAGAN-PC\SQLEXPRESS;Initial Catalog=update_test;Integrated Security=True");
SqlCommand cmd;
protected void Page_Load(object sender, EventArgs e)
{
}
protected void delete_button_Click(object sender, EventArgs e)
{
con.Open();
cmd = new SqlCommand("delete from update_delete where id like'"+TextBox1.Text+"'",con);
cmd.ExecuteNonQuery();
Response.Write("Control reached.");
con.Close();
Response.Write("Data successfully deleted.");
}
protected void update_button_Click(object sender, EventArgs e)
{
con.Open();
cmd = new SqlCommand("update update_delete set password ='"+TextBox3.Text+"' where id like'"+TextBox2+"'", con);
cmd.ExecuteNonQuery();
Response.Write("Control reached.");
con.Close();
Response.Write("Data successfully Updated.");
}
}
I am trying to implement update query but there is a little problem in it. I have used SQL Server as database and update_delete is a table in which there are 3 columns id,sname,password and I am trying to update password with respect to id.
Problem is when I click on update button control reaches cmd.ExecuteNonQuery(); no error is displayed. but updating is not taking place. what should I do. Please Please Please help me. Thanks in advance. :) :)

Answer 1

I'm just guessing here - if Id is a numeric datatype, then you cannot use LIKE with it.
Also: please use using()... blocks to ensure proper disposal and use parametrized queries to avoid SQL Injection attacks.
Write your UPDATE command like this:
protected void update_button_Click(object sender, EventArgs e)
{
// get the values to use
string idValue = Convert.ToInt32(TextBox3.Text.Trim());
string password = TextBox2.Text.Trim();
// define the query text with *parameters* !
string updateQuery = "update update_delete set password = #password where id = #ID";
// put things like SqlConnection and SqlCommand into "using()...." blocks
using (SqlCommand updCmd = new SqlCommand(updateQuery, con))
{
// define parameters and their values
updCmd.Parameters.Add("#password", SqlDbType.VarChar, 50).Value = password;
updCmd.Parameters.Add("#ID", SqlDbType.Int).Value = idValue;
con.Open();
cmd.ExecuteNonQuery();
con.Close();
Response.Write("Data successfully Updated.");
}
}

Answer 2

I suppose you get an Exception. I would kindly suggest to catch your exception and tell us the message... You can catch the exception using the debugger or a try-catch clause.
If you don't get an exception and "Control reached" message is displayed, you would have to use the formed SQL string to use it directly in SQL Server and see if there is a mistake in the SQL statement. I suppose that you somehow form an invalid SQL statement (eg using a non-existing ID).
Hope I helped!