Mathieu said:
When the configuration window is open, I want it to be on top, and the other
would
be locked.
It locks the main window, so yes

)
TopMost does not 'lock' the main window
What do you mean by "Modal window" ?
I have tried the TopMost property, and it locks the main window, but it
seems that your solution is doing the same. So, I will take a look at
ShowDialog(), and see if I have another question

)
Thanks.
Try this for an example:
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
namespace WinScratch
{
/// <summary>
/// Summary description for Form1.
/// </summary>
public class Form1 : System.Windows.Forms.Form
{
private System.Windows.Forms.Button button1;
private System.Windows.Forms.Button button2;
/// <summary>
/// Required designer variable.
/// </summary>
private System.ComponentModel.Container components = null;
public Form1()
{
//
// Required for Windows Form Designer support
//
InitializeComponent();
//
// TODO: Add any constructor code after InitializeComponent call
//
}
/// <summary>
/// Clean up any resources being used.
/// </summary>
protected override void Dispose( bool disposing )
{
if( disposing )
{
if (components != null)
{
components.Dispose();
}
}
base.Dispose( disposing );
}
#region Windows Form Designer generated code
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.button1 = new System.Windows.Forms.Button();
this.button2 = new System.Windows.Forms.Button();
this.SuspendLayout();
//
// button1
//
this.button1.Location = new System.Drawing.Point(8, 8);
this.button1.Name = "button1";
this.button1.Size = new System.Drawing.Size(96, 23);
this.button1.TabIndex = 0;
this.button1.Text = "Show Modal";
this.button1.Click += new System.EventHandler(this.button1_Click);
//
// button2
//
this.button2.Location = new System.Drawing.Point(112, 8);
this.button2.Name = "button2";
this.button2.Size = new System.Drawing.Size(96, 23);
this.button2.TabIndex = 1;
this.button2.Text = "Show TopMost";
this.button2.Click += new System.EventHandler(this.button2_Click);
//
// Form1
//
this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
this.ClientSize = new System.Drawing.Size(216, 38);
this.Controls.Add(this.button2);
this.Controls.Add(this.button1);
this.Name = "Form1";
this.Text = "Form1";
this.ResumeLayout(false);
}
#endregion
/// <summary>
/// The main entry point for the application.
/// </summary>
[STAThread]
static void Main()
{
Application.Run(new Form1());
}
private void button1_Click(object sender, System.EventArgs e)
{
Form newForm = new Form();
newForm.Text = "Modal Window";
newForm.ShowDialog();
}
private void button2_Click(object sender, System.EventArgs e)
{
Form newForm = new Form();
newForm.Text = "TopMost Form";
newForm.TopMost = true;
newForm.Show();
}
}
}