Measure a String without using a Graphics object?

Question

I am using pixels as the unit for my font. In one place, I am performing a hit test to check if the user has clicked within the bounding rectangle of some text on screen. I need to use something like MeasureString for this. Unfortunately, the code doing the hit test is deep within a library which does not have access to a Graphics object or even a Control.

How do I get the bounding box of a string given the font without using the Graphics class? Why do I even need a Graphics object when my font is in pixels?

Answer 1

If you have a reference to System.Windows.Forms, try using the TextRenderer class. There is a static method which takes the string and font and returns the size. MSDN Link

Answer 2

You don't need to use the graphics object that you are using to render to do the measuring. You could create a static utility class:

public static class GraphicsHelper
{
    public static SizeF MeasureString(string s, Font font)
    {
        SizeF result;
        using (var image = new Bitmap(0, 0))
        {
            using (var g = Graphics.FromImage(image))
            {
                result = g.MeasureString(s, font);
            }
        }

        return result;
    }
}

It might be worthwile, depending on your situation to set the dpi of the bitmap as well.