Determine Label Size based upon amount of text and font size in Winforms/C#

Question

Hi there,

I'd like to know if there's a better approach to this problem. I want to resize a label (vertically) to accomodate certain amount of text. My label has a fixed width (about 60 chars wide before it must wrap), about 495 pixels. The font is also a fixed size (12points afaik), but the text is not.

What I want to do is increase the Label Height when there's a "NewLine" or the text must wrap; the idea is that the text is fully visible in the label. The AutoSize doesn't work because it will grow in width, not in height.

Of course I could count the number of NewLines and add: Newlines * LineHeight, and then -given that I manage to put 60 chars per line, just divide the number of chars and add as many LineHeight pixels as needed.

I was wondering if there was a more professional way to do it. Is my approach too "lame" ?

Thanks in advance.

Answer 1

Graphics.MeasureString() will probably help you.

This is also one of the only usecases for using the Control.CreateGraphics() call!

Answer 2

How about Graphics.MeasureString, with the overload that accepts a string, the font, and the max width? This returns a SizeF, so you can round round-off the Height.

        using(Graphics g = CreateGraphics()) {
            SizeF size = g.MeasureString(text, lbl.Font, 495);
            lbl.Height = (int) Math.Ceiling(size.Height);
            lbl.Text = text;
        }

Answer 3

System.Drawing.Graphics has a MeasureString method that you can use for this purpose. Use the overload that takes a string, a font, and an int "width" parameter; this last parameter specifies the maximum width allowed for the string - use the set width of your label for this parameter.

MeasureString returns a SizeF object. Use the Height property of this returned object to set the height of your label.

Note: to get a Graphics object for this purpose, you can call this.CreateGraphics.

Answer 4

Well the 60 chars might be valid for your test text, but not all characters have the same width. For instance, compare
llllllllllllllllllllllllllllllllllllllllllllllllllllllllllll
and
wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww

They both have 60 characters, and yet have vastly differing widths.

Answer 5

Is there any downside to using the TextRenderer class to measure the string (like in Marc's response) instead of going through the work to create a Graphics object, etc?

Answer 6

This "answer" is for future reference and to combat the initial assumption that AutoSize = true implies that it (a WinForms label) will never grow in height.

The following link shows the various effects of AutoSize = true with other properties such as MaximumSize. Depending upon the expected use of the question it may be appropriate to follow one of these approaches.

http://blogs.msdn.com/jfoscoding/articles/478299.aspx