In the Windows Forms documentation for Control.SuspendLayout(), there is the following statement:
There must be no pending calls to SuspendLayout for ResumeLayout to be successfully called.
There's a few loaded phrases in this statement (such as "pending calls").
see: https://docs.microsoft.com/en-us/dotnet/api/system.windows.forms.control.suspendlayout?view=net-5.0
What they are saying is, you must call ResumeLayout one-for-one with SuspendLayout.
So, to guard against this state, you could do this:
MyControl.SuspendLayout();
try
{
// do some work
}
finally
{
MyControl.ResumeLayout();
}
That way if the "do some work" block throws an exception, you can be assured that ResumeLayout is always called, otherwise the suspend/resume will become unbalanced and your UI will not update properly.
In other words, if you do this:
MyControl.SuspendLayout();
MyControl.SuspendLayout();
MyControl.ResumeLayout();
then ResumeLayout will not have the desired affect.
But, this will:
MyControl.SuspendLayout();
MyControl.SuspendLayout();
MyControl.ResumeLayout();
MyControl.ResumeLayout();