How do i get the size of a font in pixels?

Question

My initial instinct is to get the current DpiY setting of the system via a Graphics instance, but I cannot figure out how to get one.

Spellunking through Reflector I see that Microsoft manages it using unsafe code:

IntPtr dC = UnsafeNativeMethods.GetDC(NativeMethods.NullHandleRef);
try
{
    using (Graphics graphics = Graphics.FromHdcInternal(dC))
    {
        float num = graphics.DpiY;
    }
}

What is the managed equivalent way to construct a Graphics when i don't have a graphics?

I tried:

using (Graphics g = Graphics.FromHdc(IntPtr.Zero))
{
    return font.GetHeight(g.DpiY);
}

But that throws a Value cannot be null exception.

Usually, when I get to the end of my question and figure out what my *real question is*, I change my title. Please review my edit to make sure I didn't muck up your question. — , Jan 17 '12 at 14:35
@Will That was sort of the point in my original question. i'm not *always* interested in the font size (e.g. control size, image size, scaling amount). i was afraid that someone might short-circuit the question, and try to use `MeasureText` to get the font height. People tend to confuse question with applicability. i've tried omitting rationale, having just my question. But people refuse to answer it without knowing *why* i want to do something. i've had thorough examples of *why*, then you have John Saunders downvote because he's grumpy (http://stackoverflow.com/q/8141795/12597) — Ian Boyd, Jan 17 '12 at 16:47
@Will Here's another good example of the problem. A guy asked the exact question i had ***LINQ where or filter c#*** (http://stackoverflow.com/questions/5954965/linq-where-or-filter-c-sharp). The answers cheated the question, answering instead the example. Today i have the exact same question, but the existing answers do not answer the question. i have to construct the exact same question (with the words in the title rearranged to look sufficiently different ***LINQ filter where or*** (http://stackoverflow.com/questions/8900131/linq-filter-where-or). — Ian Boyd, Jan 17 '12 at 19:05

LarsTech · Accepted Answer · 2012-01-17T14:55:14.197

1

You can try using the TextRendering method which does not use a Graphics object:

int textHeight = TextRenderer.MeasureText("Text", this.Font).Height;

Or if need be, you can make your own quick Graphic:

float textHeight;
using (Bitmap b = new Bitmap(1,1))
using (Graphics g = Graphics.FromImage(b)) {
  textHeight = this.Font.GetHeight(g.DpiY);
}

edited Jan 17 '12 at 14:55

answered Jan 17 '12 at 14:47

LarsTech

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i was concerned that a Bitmap's resolution is not guaranteed to be created at the current system dpi setting (i.e. a lot of drawing systems create a graphic at 72 dpi). But it seems to match the system resolution upon `Bitmap` creation. – Ian Boyd Jan 17 '12 at 19:01

How do i get the size of a font in pixels?

1 Answers1