How do I know if a WPF window is opened

Question

In a WPF window, how do I know if it is opened?

My goal to open only 1 instance of the window at the time.

So, my pseudo code in the parent window is:

if (this.m_myWindow != null) {     if (this.m_myWindow.ISOPENED) return; }  this.m_myWindow = new MyWindow(); this.m_myWindow.Show(); 

EDIT:

I found a solution that solves my initial problem. window.ShowDialog();

It blocks the user from opening any other window, just like a modal popup. Using this command, it is not necessary to check if the window is already open.

Answer 1

In WPF there is a collection of the open Windows in the Application class, you could make a helper method to check if the window is open.

Here is an example that will check if any Window of a certain Type or if a Window with a certain name is open, or both.

public static bool IsWindowOpen<T>(string name = "") where T : Window {     return string.IsNullOrEmpty(name)        ? Application.Current.Windows.OfType<T>().Any()        : Application.Current.Windows.OfType<T>().Any(w => w.Name.Equals(name)); } 

Usage:

if (Helpers.IsWindowOpen<Window>("MyWindowName")) {    // MyWindowName is open }  if (Helpers.IsWindowOpen<MyCustomWindowType>()) {     // There is a MyCustomWindowType window open }  if (Helpers.IsWindowOpen<MyCustomWindowType>("CustomWindowName")) {     // There is a MyCustomWindowType window named CustomWindowName open }