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Is there a way to make the message box bigger?

Thanks,
          Andy

invoke MessageBox,0,OFFSET successtext,OFFSET started,MB_OK

Hey Andy,

To modify the MessageBox's size you'll need to setup a custom window handler for the MessageBox using a process wide hook. It's not really as hard as it sounds, check out this pseudo/asm code.

.DATA
handleMsgBox	DWORD 0

.CODE
CSMsgBoxProc PROC nCode:DWORD, wParam:WPARAM, lParam:LPARAM
LOCAL handleThis:DWORD

	MOV EAX, nCode
	CMP EAX, HCBT_ACTIVATE
	JNE CALLNEXT
		MOV EAX, wParam
		MOV handleThis, EAX

		; MODIFY SIZE HERE

		XOR EAX, EAX
		RET
	CALLNEXT:
	PUSH lParam
	PUSH wParam
	PUSH nCode
	PUSH handleThis
	CALL CallNextHookEx
	RET
	
CSMsgBoxProc ENDP

CSMsgBox PROC hParent:DWORD, strMessage:DWORD, strTitle:DWORD, nStyle:DWORD
LOCAL dwReturn:DWORD

	CALL GetCurrentThreadId
	PUSH EAX
	PUSH 0
	PUSH OFFSET CSMsgBoxProc
	PUSH WH_CBT
	CALL SetWindowsHookEx
	MOV handleMsgBox, EAX

	PUSH nStyle
	PUSH strTitle
	PUSH strMessage
	PUSH handleParent
	CALL MessageBox
	MOV dwReturn, EAX

	PUSH handleMsgBox
	CALL UnhookWindowsHookEx

	MOV EAX, dwReturn
	RET

CSMsgBox ENDP

Just a bit of a warning, you get a performance penalty with each hook/wndproc/etc you install. Each one means you are going to be receiving more messages which need to be processed. The example uses a process wide hook because a system wide hook would send you all messages killing execution time. Process wide hooks only get those of the current process. Also it's even more simplified/optimized by only receiving the computer based training messages (WH_CBT) which means you aren't being sent a majority of the messages you normally would when using journal hooks. You should be able to take the above code, insert your sizing code where specified, then just call CSMsgBox instead of MessageBox. But there are no guarantees as I've not tested the code at all.

Regards,
Bryant Keller

If you want predictable behavior you'll need to use hooks. Otherwise the same messagebox will look different from user to user because of font sizes, resolution, custom shell styles, etc.

Other solution is to use customizable task dialogs (they kinda supersede messageboxes), but these are only available on Vista/win7.