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TextBlock.LineHeight Property

Definition

Gets or sets the height of each line of content.

public:
 property double LineHeight { double get(); void set(double value); };
[System.ComponentModel.TypeConverter(typeof(System.Windows.LengthConverter))]
public double LineHeight { get; set; }
[<System.ComponentModel.TypeConverter(typeof(System.Windows.LengthConverter))>]
member this.LineHeight : double with get, set
Public Property LineHeight As Double

Property Value

The height of line, in device independent pixels, in the range of 0.0034 to 160000. A value of NaN (equivalent to an attribute value of "Auto") indicates that the line height is determined automatically from the current font characteristics. The default is NaN.

Attributes

Exceptions

LineHeight is set to a non-positive value.

Examples

The following example shows how to set the LineHeight attribute of a TextBlock element.

<TextBlock 
  Name="textBlock"
  
  Background="AntiqueWhite" 
  Foreground="Navy" 
  
  FontFamily="Century Gothic"
  FontSize="12"
  FontStretch="UltraExpanded"
  FontStyle="Italic"
  FontWeight="UltraBold"
  
  LineHeight="Auto"
  Padding="5,10,5,10"
  TextAlignment="Center"
  TextWrapping="Wrap"
  
  Typography.NumeralStyle="OldStyle"
  Typography.SlashedZero="True"
>
  <Run Background="LightGreen">Text run 1.</Run>
  <LineBreak/><Run Background="LightBlue">Text run 2.</Run>
  <LineBreak/><Run Background="LightYellow">Text run 3.</Run>
</TextBlock>

The following example shows how to set the LineHeight property programmatically.

TextBlock textBlock = new TextBlock(new Run("A bit of text content..."));

textBlock.Background              = Brushes.AntiqueWhite;
textBlock.Foreground              = Brushes.Navy;

textBlock.FontFamily              = new FontFamily("Century Gothic");
textBlock.FontSize                = 12;
textBlock.FontStretch             = FontStretches.UltraExpanded;
textBlock.FontStyle               = FontStyles.Italic;
textBlock.FontWeight              = FontWeights.UltraBold;

textBlock.LineHeight              = Double.NaN;
textBlock.Padding                 = new Thickness(5, 10, 5, 10);
textBlock.TextAlignment           = TextAlignment.Center;
textBlock.TextWrapping            = TextWrapping.Wrap;

textBlock.Typography.NumeralStyle = FontNumeralStyle.OldStyle;
textBlock.Typography.SlashedZero  = true;
Dim textBlock As New TextBlock(New Run("A bit of text content..."))

textBlock.Background = Brushes.AntiqueWhite
textBlock.Foreground = Brushes.Navy

textBlock.FontFamily = New FontFamily("Century Gothic")
textBlock.FontSize = 12
textBlock.FontStretch = FontStretches.UltraExpanded
textBlock.FontStyle = FontStyles.Italic
textBlock.FontWeight = FontWeights.UltraBold

textBlock.LineHeight = Double.NaN
textBlock.Padding = New Thickness(5, 10, 5, 10)
textBlock.TextAlignment = TextAlignment.Center
textBlock.TextWrapping = TextWrapping.Wrap

textBlock.Typography.NumeralStyle = FontNumeralStyle.OldStyle
textBlock.Typography.SlashedZero = True

Remarks

Changing this value does not change the height of the associated text; rather, it changes the height of the line that contains the text. To change the size of the text, use the FontSize property.

In addition to this property, the layout of lines in a TextBlock is affected by its LineStackingStrategy property.

This dependency property also has an attached property usage. In XAML, the usage is <object TextBlock.LineHeight="value".../>, where object is an object element (typically a flow element) contained within a TextBlock, and value is a string as explained in XAML Values. In code, the attached property usage is supported by GetLineHeight and SetLineHeight. The attached property usage is not common.

XAML Attribute Usage

<object LineHeight="double"/>  
- or -  
<object LineHeight="qualifiedDouble"/>  
- or -  
<object LineHeight="Auto"/>  

XAML Values

double
Double

String representation of a Double value equal to or greater than 0.0034 and equal to or less then 160000. An unqualified value is measured in device independent pixels. Strings need not explicitly include decimal points.

qualifiedDouble
A double value as described above, (excepting Auto) followed by one of the following unit specifiers: 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

Auto
Causes the line height to be determined automatically from the current font characteristics. Equivalent to a property value of Double.NaN.

Dependency Property Information

Identifier field LineHeightProperty
Metadata properties set to true AffectsMeasure, AffectsRender, Inherits

Applies to

See also