System.Drawing.Font.GetHeight() Exception

[JurkMonkey]

	"   at System.Drawing.Font.GetHeight(Graphics graphics)\r\n   at System.Drawing.Font.GetHeight()\r\n   at System.Drawing.Font.get_Height()\r\n   at System.Windows.Forms.Control.get_FontHeight()\r\n   at System.Windows.Forms.ComboBox.get_PreferredHeight()\r\n   at System.Windows.Forms.ComboBox.get_DefaultSize()\r\n   at System.Windows.Forms.Control..ctor()\r\n   at System.Windows.Forms.ListControl..ctor()\r\n   at System.Windows.Forms.ComboBox..ctor()\r\n   at

So I was fighting with this little error for a while. Nobody had a good answer for that. Someone wrote about a font being corrupt after installing office 2007 but that didn't help me either.

What ended up happening is this:

I have a drawing class that manipulates an image using GDI+
In order to draw text I passed in a Font from my main control to draw with. After closing my image I Disposed of that font. Turns out I was disposing the reference to the font that I passed in so now the base control's font was disposed.

When I tried to create a new control on my base control I started getting an error in InitializeComponent() - specifically while trying to create a ComboBox. So now I just orphan the reference to that font ( = null ) rather than dispose of it. The base class will dispose of it correctly when it's ready.

Just thought it's handy for anyone else who runs into this one.

 

[TipGiver]

> I was disposing the reference to the font that I passed in <

I dont work with C# ... only when I have to.
You said that you passed the reference. You mean that you passed a pointer... right ?

 

[JurkMonkey]

Apparently when you pass something into a method it acts on the low level like a pointer unless you specify byval in which, a copy of that object will be passed in.

 

[TipGiver]

Yes, In VB the "local copy" is defined as ByVal, whereas the memory location.. as ByRef (pointer in C)