Resize font so text fills entire label

[Joe]

I have a label control that will be filled with text at runtime. The
length of the text will vary, but the label must stay the same size. Is
there a way to set the font size of the text such that it completely
fills the label?

For example, if the text is "Santa Claus" the font size might have to be
130 points to fill up a 637x476 label, where if the text is "Once upon a
midnight dreary / while I pondered weak and weary / over many a quaint
and curious volume of forgotten lore" the font size might have to be 40
points to fill up the 637x476 label.

I've seen a lot online about sizing a control to match text length, but
nothing about sizing text to match a control. BTW, I don't have to use a
label control - if another control will help accomplish my task, great.

Thanks,

Joe

 

[Bob Powell [MVP]]

This is an oft' asked question.

There is no simple solution. The way to go is to use MeasureString with
different font sizes and see what sort of rectangle it returns.

An adaptation of the binary search can be used to select a rectangle of the
correct size by changing the font size.

http://en.wikipedia.org/wiki/Binary_search

--
Bob Powell [MVP]
Visual C#, System.Drawing

Ramuseco Limited .NET consulting
http://www.ramuseco.com

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[Joe]

Great, thank you.

Joe

 

[Armin Zingler]

I have a label control that will be filled with text at runtime. The length
of the text will vary, but the label must stay the same size. Is there a
way to set the font size of the text such that it completely fills the
label?

For example, if the text is "Santa Claus" the font size might have to be
130 points to fill up a 637x476 label, where if the text is "Once upon a
midnight dreary / while I pondered weak and weary / over many a quaint and
curious volume of forgotten lore" the font size might have to be 40 points
to fill up the 637x476 label.

I've seen a lot online about sizing a control to match text length, but
nothing about sizing text to match a control. BTW, I don't have to use a
label control - if another control will help accomplish my task, great.

Put a label and a textbox on a Form. This works quite well:

Private Sub TextBox1_TextChanged( _
ByVal sender As System.Object, _
ByVal e As System.EventArgs) _
Handles TextBox1.TextChanged

Dim f As Font
Dim g As Graphics
Dim s As SizeF
Dim Faktor, FaktorX, FaktorY As Single

If TextBox1.Text.Length = 0 Then Return

g = Me.Label1.CreateGraphics
s = g.MeasureString(TextBox1.Text, Label1.Font)
g.Dispose()

FaktorX = Label1.Width / s.Width
FaktorY = Label1.Height / s.Height

If FaktorX > FaktorY Then
Faktor = FaktorY
Else
Faktor = FaktorX
End If

f = Label1.Font
Label1.Font = New Font(f.Name, f.SizeInPoints * Faktor)

Me.Text = Label1.Font.SizeInPoints.ToString
Label1.Text = TextBox1.Text

End Sub


Type into the textbox and the code fits the text into the label.


Armin

 

[Joe]

Thanks Armin. This works perfectly for a single line of text - I'll
certainly hang on to it. Unfortunately it doesn't take word wrapping
into consideration, so it won't work for my current application.

Joe

 

[Armin Zingler]

Thanks Armin. This works perfectly for a single line of text - I'll
certainly hang on to it. Unfortunately it doesn't take word wrapping
into consideration, so it won't work for my current application.

I tried it with a multiline textbox and it works perfectly, too.


Armin

 

[Joe]

The code you posted will work if multiple lines (ending with carriage
returns) are entered in the textbox, but not with text that's wrapped
automatically without carriage returns.

I was able to resolve that with a minor change from:

s = g.MeasureString(TextBox1.Text, Label1.Font)

to

s = g.MeasureString(TextBox1.Text, Label1.Font, Label1.Width)


Thanks again!

Joe

 

[Armin Zingler]

The code you posted will work if multiple lines (ending with
carriage returns) are entered in the textbox, but not with text
that's wrapped automatically without carriage returns.

Which wrapped text? In a string, there is no wrapped text, and in the label,
you don't want to have wrapped text.


Armin