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FlowDocument.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 each line, in device independent pixels, in the range 0.0034 to 160000. A value of NaN (equivalent to an attribute value of "Auto") causes the line height to be 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 FlowDocument element.

<FlowDocumentReader>
  <FlowDocument
    FontSize="24"
    LineHeight="48"
  >
    <Paragraph TextAlignment="Left" Background="AliceBlue">
      One<LineBreak/>
      two two<LineBreak/>
      Three Three Three<LineBreak/>
      four four four four<LineBreak/>
      Five Five Five Five Five
    </Paragraph>
  </FlowDocument>
</FlowDocumentReader>

The following figure shows how the preceding FlowDocument renders.

Screenshot: FlowDocument LineHeight

The following figure shows how the same FlowDocument renders with the default setting of LineHeight=Double.NaN.

Screenshot: FlowDocument LineHeight default

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

FlowDocument flowDoc = new FlowDocument(new Paragraph(new Run("A bit of text content...")));
// Set the content flow direction to left-to-right.
flowDoc.LineHeight = 48;
Dim flowDoc As New FlowDocument(New Paragraph(New Run("A bit of text content...")))
' Set the content flow direction to left-to-right.
flowDoc.LineHeight = 48

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 FlowDocument is affected by its LineStackingStrategy property.

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