Check connection to database in thread - database

Question

how to check connection to database while login form is showing to user before show all tools on the login form ?
In an application, I plan to arrange the following steps:
1-Login form without any special tools except a label and background image (similar to a Splash form).
2. Behind the login form (preferably inside a thread) is the connection to the server, and the user see a label with this text: try to connect to database...
3. If a connection is established (flag == right), a series of tools will be displayed for login user.
4. If the connection to the server is not established (flag == false), a series of other tools will be displayed to user for addressing the server.
I hope I could clearly make it.
using System;
using System.Windows.Forms;
using Microsoft.Data.ConnectionUI;
using System.Reflection;
public partial class LoginForm : Form
{
public LoginForm()
{
this.DoubleBuffered = true;
InitializeComponent();
System.Threading.Thread t = new System.Threading.Thread(new System.Threading.ThreadStart(CheckConnection));
t.Start();
System.Threading.Thread.Sleep(5000);
t.Abort();
}
bool flag;
private void CheckConnection()
{
using (System.Data.SqlClient.SqlConnection connection =
new System.Data.SqlClient.SqlConnection
(connectionString))
{
try
{
connection.Open();
connection.Close();
flag = true;
}
catch
{
flag = false;
}
}
}
private void SplashScreenForm_Load(object sender, EventArgs e)
{
if (flag)
{
//Do somethings to login user
}
else
{
//Do something to create connection to database
}
}
The problem with this code is that the thread starts running before the form is displayed, and the program initially starts with a delay and immediately all the tool is displayed. Thanks for giving friends guidance.

Answer 1

I used Backgroundworker controller to solve this problem. It works very excellent.
Refer to https://learn.microsoft.com/en-us/dotnet/api/system.componentmodel.backgroundworker?view=netframework-4.8