winforms - Out of memory exception in CreateGraphics (GdipCreateFromHWND) -

on machines vary in configuration (os, graphics card , memory) outofmemory exception. tests showed there no significant increase in virtual memory consumed. that's piece of code exception raised:

public override size getpreferredsize(size proposedsize) {     try     {         using (graphics g = this.creategraphics())         {             sizef measured = g.measurestring(this.text, this.font); // <= outofmemoryexception             measured += new sizef(1, 1);             return measured.tosize();         }     }     catch (outofmemoryexception oom)     {         system.diagnostics.trace.writeline(oom.tostring());     }     return proposedsize; } 

the class derived directly label.

creategraphics() makes call gdi+ function gdipcreatefromhwnd in cases return status (3) raises outofmemoryexception face:

[editorbrowsable(editorbrowsablestate.advanced), securitypermission(securityaction.linkdemand, flags=securitypermissionflag.unmanagedcode)] public static graphics fromhwndinternal(intptr hwnd) {     intptr 0 = intptr.zero;     int status = safenativemethods.gdip.gdipcreatefromhwnd(new handleref(null, hwnd), out zero);     if (status != 0)     {         throw safenativemethods.gdip.statusexception(status); // status = 3 throws outofmemoryexception text "out of memory"     }     return new graphics(zero); } 

but unfortunately have not found documentation on function , cases when returns out of memory.

the issue @ least repeatable on 1 customers machine fast. has click on button creates new window 1 of derived label placed , used display content in webbrowser control.

if have ideas me find reasons of exception great!

cheers, michael

this might work:

private graphics _graphics; protected override void onpaint(painteventargs e) {     _graphics = e.graphics;     base.onpaint(e); }  public override size getpreferredsize(size proposedsize) {     try     {         sizef measured = _graphics.measurestring(this.text, this.font);         measured += new sizef(1, 1);         return measured.tosize();     }     catch (outofmemoryexception oom)     {         system.diagnostics.trace.writeline(oom.tostring());     }     return proposedsize; } 

the documentation @ http://msdn.microsoft.com/en-us/library/system.windows.forms.control.creategraphics.aspx states "you cannot cache graphics object reuse, except use non-visual methods graphics.measurestring", trying do. fail if getpreferredsize called before control painted, , you'll want dispose graphics object, maybe closer viable solution.