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.NET Framework Class Library
ControlFontSize Property

Gets or sets the font size.

Namespace:   System.Windows.Controls
Assembly:  PresentationFramework (in PresentationFramework.dll)
<[%$TOPIC/ms592514_en-us_VS_110_1_0_0_0_0%](GetType([%$TOPIC/ms592514_en-us_VS_110_1_0_0_0_1%]))> _
<[%$TOPIC/ms592514_en-us_VS_110_1_0_0_0_2%](True)> _
<[%$TOPIC/ms592514_en-us_VS_110_1_0_0_0_3%]([%$TOPIC/ms592514_en-us_VS_110_1_0_0_0_4%].None)> _
Public Property FontSize As [%$TOPIC/ms592514_en-us_VS_110_1_0_0_0_5%]
public [%$TOPIC/ms592514_en-us_VS_110_1_0_1_0_5%] FontSize { get; set; }
property [%$TOPIC/ms592514_en-us_VS_110_1_0_2_0_5%] FontSize {
	[%$TOPIC/ms592514_en-us_VS_110_1_0_2_0_6%] get ();
	void set ([%$TOPIC/ms592514_en-us_VS_110_1_0_2_0_7%] value);
member FontSize : [%$TOPIC/ms592514_en-us_VS_110_1_0_3_0_5%] with get, set
function get FontSize () : [%$TOPIC/ms592514_en-us_VS_110_1_0_4_0_0%] 
function set FontSize (value : [%$TOPIC/ms592514_en-us_VS_110_1_0_4_0_1%])
<object FontSize="double"/>
- or –
<object FontSize ="qualifiedDouble"/>

XAML Values



A string representation of a Double value. This is interpreted as a device-independent unit (1/96th inch) measurement. Strings need not explicitly include decimal points. For example, a value of 1 is acceptable.

The same Double range restrictions that are mentioned in the Property Value section apply here.


A double value as previously described that is followed by one of these unit declaration strings: px, in, cm, pt.

px (default) is device-independent units (1/96th inch per unit)

in is inches; 1in==96px

cm is centimeters; 1cm==(96/2.54) px

pt is points; 1pt==(96/72) px

Note   In many cases a double may be set to "Auto," but a ControlFontSize does not render if set to "Auto".

Property Value

Type: SystemDouble
The size of the text in the Control. The default is SystemFontsMessageFontSize. The font size must be a positive number.

This property only affects a control whose template uses the FontSize property as a parameter. On other controls, this property has no impact.


The following example shows how to set the font size property of a control.

<Button Name="btn3" FontSize="10.0" 
Private Sub ChangeFontSize(ByVal Sender As Object, ByVal e As RoutedEventArgs)

    fsize = btn3.FontSize
    If (fsize = 16.0) Then

        btn3.FontSize = 10.0
        btn3.Content = "FontSize" 


        btn3.FontSize = 16.0
        btn3.Content = "Control font size changes from 10 to 16." 
    End If 
End Sub
void ChangeFontSize(object sender, RoutedEventArgs e)
    fsize = btn3.FontSize;
    if (fsize == 16.0)
        btn3.FontSize = 10.0;
        btn3.Content = "FontSize";
        btn3.FontSize = 16.0;
        btn3.Content = "Control font size changes from 10 to 16.";
Version Information

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1