where to add connection string of SQL server in asp.net page - asp.net

Question

I am having an ASP.NET page that is containing the textboxes namely username and password and a button named cmdlogin. I want that when I enter the data in text boxes then that data should be saved into the database.
In SQL server of Visual studio, I have created table and even also have given the
INSERT INTO cmd_login VALUES(".......").
Now the problem is when I entered the data in textbooxes it is not saved in the database table. what can I do.
I have put my connection string into the class file. Do I need to put my connection string in the web.config?
my code is
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data.SqlClient;
public class Db
{
public static SqlConnection GetConnection()
{
SqlConnection cn = new SqlConnection();
cn.ConnectionString =#"Data Source=.\SQLEXPRESS;AttachDbFilename=E:\talat\MyRealSacaProject\App_Data\SACALogin.mdf;Inte grated Security=True;User Instance=True;";
cn.Open();
return cn;
}
public static void SaveAdmin(admin a)
{
SqlConnection cn = GetConnection();
string sql = "INSERT INTO admin_login VALUES(#[User-Name],#Password)";
SqlCommand cmd = new SqlCommand(sql, cn);
cmd.Parameters.AddWithValue("#[User-Name]",a.username);
cmd.Parameters.AddWithValue("#Password", a.password);
cmd.ExecuteNonQuery();
cn.Close();
}
}

Answer 1

try this simple code:
SqlConnection _conn = new SqlConnection(_connString);
_conn.Open();
SqlCommand _cmd = new SqlCommand();
_cmd.CommandType = CommandType.StoredProcedure;
_cmd.Parameters.Clear();
_cmd.Connection = _conn;
_cmd.CommandText = "INSERT INTO [tablename] VALUE ([fieldvalue])"; //here your textbox
int _execute = _cmd.ExecuteNonQuery();
bool _result = false;
if(_execute != 1)
_result = true;
_conn.Close();

Answer 2

chnage your code as given below, it will work
public static SqlConnection GetConnection()
{
string ConString="Data Source=.\SQLEXPRESS;AttachDbFilename=E:\talat\MyRealSacaProject\App_Data\SACALogin.mdf;Integrated Security=True;User Instance=True";
SqlConnection cn = new SqlConnection(ConString);
cn.Open();
return cn;
}

Answer 3

try this change from your code :
public static void SaveAdmin(admin a)
{
SqlConnection cn = GetConnection();
string sql = "INSERT INTO admin_login VALUES('" + a.username + "','" + a.Password + "')";
SqlCommand cmd = new SqlCommand(sql, cn);
cmd.ExecuteNonQuery();
cn.Close();
}