Detecting font size in an edit control

[annelinn]

I'm looking for a way to reliably work out how many characters will fit into an edit control, using a monospaced font like Courier New.

; Create an edit control, 400x200 pixels
$handle = GUICtrlCreateEdit("", 0, 0, 400, 200, BitOR($ES_MULTILINE, $ES_READONLY, $WS_VSCROLL, $WS_BORDER))

; Use monospaced Courier New font, size 9
GUICtrlSetFont($handle, 9, 400, 0, "Courier New")

; Display a message
_GUICtrlEdit_AppendText($handle, "Hello world!")

This code will create the edit control.

Alas, the font size of "9" doesn't tell me how many characters I can actually fit on each line (and how many lines I can fit in the control).

(Characters of this size are acutally 7 pixels wide and 15 pixels high.)

The solution I'm looking for is any of the following:

(1) A way to convert <font name> and <font size> into <font actual width> and <font actual height>

(2) A way to convert <window width in pixels> and <window height in pixels> into <max columns> and <max rows>

(3) Some web page that lists the actual sizes of standard Windows fonts

I've spent hours trying each solution in turn, with no success. Can anyone help?

[Richard Robertson]

http://msdn.microsoft.com/en-us/library/dd144938%28VS.85%29.aspx

The device context for the first parameter would come from the edit box.

[annelinn]

Forgive a n00b question: I know little about C/C#.

How can I call the MSDN function in the above link from within an AutoIt script?

Here's my best guess. The link says the function, GetTextExtentPoint32(), returns a "size structure".

That's meaningless to me, and the AutoIT help file for DllCall() doesn't specify that kind of data type, or how to deal with it.

$result = DllCall("Gdi32.dll", "size", "GetTextExtentPoint32", "str", "hello world")

Edited August 7, 2010 by annelinn