I have been coding error it is not connecting to my mysql database

Is shows error:

'Basic.exe' (CoreCLR: DefaultDomain): Loaded 'C:\Program Files\dotnet\shared\Microsoft.NETCore.App\6.0.3\System.Private.CoreLib.dll'. Skipped loading symbols.

The module is optimized and the debugger option 'Just My Code' is enabled.

The thread 0x23ec has exited with code 0 (0x0). The thread 0x35bc has exited with code 0 (0x0). The thread 0x3b6c has exited with code 0 (0x0).

The thread 0x1274 has exited with code 0 (0x0).

The program '[10052] Basic.exe' has exited with code 0 (0x0).

private void button6_Click(object sender, EventArgs e)
{
    SqlConnection con -new SqlConnection("Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=C:\Users\Administrator\source\MySQL\testDB.mdf;Integrated Security=True;Connect Timeout=30");
    con.Open();
    SqlCommand cmd = new SqlCommand("insert into testDb.employee values (@employee_id,@employee_name,@employee_salary)", con);
    cmd.Parameters.AddWithValue("@employee_id", int.Parse(textBox6.Text));
    cmd.Parameters.AddWithValue("@employee_name", textBox7.Text);
    cmd.Parameters.AddWithValue("@employee_salary", int.Parse(textBox8.Text));
    cmd.ExecuteNonQuery();
    con.Close();
    MessageBox.Show("Successfully Record Saved");
}

My SQL Database:

SELECT FROM testdb.employee;
insert into testDB.employee(employee_id,employee_name,employee_salary) Values ('123','RAFI','10000')
insert into testDB.employee(employee_id,employee_name,employee_salary) Values ('456','RAJESH','20000')
insert into testDB.employee(employee_id,employee_name,employee_salary) Values ('789','RAMESH','30000')
select from testDB.employee

emp_id employee_name employee_salary

123 RAFI 10000

456 RAJESH 20000

789 RAMESH 30000