How to prevent opening a form multiple time in C#?

Question

I have a form from that form i have programatically open a another form i want to avoid that another form not open multiple time... so how to do it???? Give me solution for that.... Thanks & Regards... atul pote...

Poppa Wallace · Answer

public static Form IsFormAlreadyOpen(Type formType) { return Application.OpenForms.Cast ().FirstOrDefault(openForm => openForm.GetType() == formType); } Button click to open window check if already open and bring to front var mcj = new NewWindow(); Form frmTest; if ((frmTest = IsFormAlreadyOpen(typeof(NewWindow))) == null) { mcj.ShowDialog(this); } else { frmTest.WindowState = FormWindowState.Normal; frmTest.BringToFront(); }