WPF TextBlock

WPF TextBlock

A TextBlock control in .NET 3.5 provides a lightweight control for displaying small amounts of flow content. This tutorial demonstrates how to create and use a TextBlock control in WPF using XAML and C#.

Creating a TextBlock

The TextBlock element represents a WPF TextBlock control in XAML.

 

<TextBlock/>

 

The Width and Height attributes of the TextBlock element represent the width and the height of a TextBlock. The Text property of the TextBlock element represents the content of a TextBlock. The Name attribute represents the name of the control, which is a unique identifier of a control. The Foreground property sets the foreground color of contents. This control does not have a Background property.

 

The code snippet in Listing 1 creates a TextBlock control and sets the name, height, width, foreground and content of a TextBlock control. Unlike a TextBox control, the TextBlock does not have a default border around it.

 

<TextBlock Name="TextBlock1" Height="30" Width="200"

    Text="Hello! I am a TextBlock." Foreground="Red">

</TextBlock>

Listing 1

The output looks like Figure 1.

Figure 1

As you can see from Figure 1, by default the TextBlock is place in the center of the page. We can place a TextBlock control where we want by using the Margin, VerticalAlignment and HorizontalAlignment attributes that sets the margin, vertical alignment, and horizontal alignment of a control.

The code snippet in Listing 2 sets the position of the TextBlock control in the left top corner of the page.

<TextBlock Name="TextBlock1" Height="30" Width="200"

        Text="Hello! I am a TextBlock."

        Margin="10,10,0,0" VerticalAlignment="Top"

        HorizontalAlignment="Left">           

</TextBlock>

Listing 2

Creating a TextBlock Dynamically

The code listed in Listing 3 creates a TextBlock control programmatically. First, it creates a TextBlock object and sets its width, height, contents and foreground and later the TextBlock is added to the LayoutRoot.

private void CreateATextBlock()

{

    TextBlock txtBlock = new TextBlock();

    txtBlock.Height = 50;

    txtBlock.Width = 200;

    txtBlock.Text = "Text Box content";

    txtBlock.Foreground = new SolidColorBrush(Colors.Red);

 

    LayoutRoot.Children.Add(txtBlock);

}

Listing 3

Setting Fonts of TextBlock Contents

The FontSize, FontFamily, FontWeight, FontStyle, and FontStretch properties are used to set the font size, family, weight, style and stretch to the text of a TextBlock. The code snippet in Listing 4 sets the font properties of a TextBlock.

FontSize="14" FontFamily="Verdana" FontWeight="Bold"

Listing 4

The new output looks like Figure 2.

Figure 2

The FontSource property allows loading custom fonts dynamically. The following code snippet sets the FontSource property.

Uri fontUri = new Uri("SomeFont.ttf", UriKind.Relative);

StreamResourceInfo MySRI = Application.GetResourceStream(fontUri);

TextBlock1.FontSource = new FontSource(MySRI.Stream);

 

Wrapping, Alignment and Padding

 

The TextWrapping property sets the wrap of no warp text. The following code snippet sets the wrapping text option.

TextWrapping="Wrap"

The TextAlignment property sets the text alignment in a TextBlock, which is of type TextAlignment enumeration. A text can be aligned left, center, or right. 

TextAlignment="Right"

The Padding property sets the space between a boundary and the text that can be applied to all sides or a selected side of the boundary. The padding spacing is based on left, right, top, and bottom. If you specify only a single value, the padding will be applied to all four sides and if you specify two values, it will be applied to LeftTop and BottomRight sides.

Listing 5 shows all these properties in a complete sample.

<TextBlock Name="TextBlock1" Height="30" Width="200"

    Text="Hello! I am a TextBlock." Foreground="Red"

    Margin="10,10,0,0" VerticalAlignment="Top"

    HorizontalAlignment="Left"

    FontSize="14" FontFamily="Verdana" FontWeight="Bold"

    TextWrapping="Wrap" TextAlignment="Center" Padding="2">

</TextBlock>

Listing 5

Inlines

 

The Inlines property represents the collection of inline text within a TextBlock control. A Run object represents an inline text and can be treated as its own text control and have its foreground and font related properties.

Listing 6 sets the Inlines property of the TextBlock and sets different fonts and foreground colors.

<TextBlock.Inlines>

    <Run FontWeight="Bold" FontSize="14" Text="Hi! I am a TextBlock. " />

    <Run FontStyle="Italic" Foreground="Red" Text="This is red text. " />

    <Run FontStyle="Italic" FontSize="18" Text="Here is some linear gradient text. ">

        <Run.Foreground>

            <LinearGradientBrush>

                <GradientStop Color="Green" Offset="0.0" />

                <GradientStop Color="Purple" Offset="0.25" />

                <GradientStop Color="Orange" Offset="0.5" />

                <GradientStop Color="Blue" Offset="0.75" />

              </LinearGradientBrush>

        </Run.Foreground>

    </Run>           

    <Run FontStyle="Italic" Foreground="Green" Text="How about adding some green? " />           

</TextBlock.Inlines>

Listing 6

The new output looks like Figure 3.

Figure 3

TextDecorations

 

The TextDecorations property represents the text decorations that are applied to the content of a TextBlock. WPF supports only underline text decoration.

Listing 7 sets the TextDecorations to underline.

<TextBlock Name="TextBlock1"     

    Margin="10,10,0,0" VerticalAlignment="Top"

    HorizontalAlignment="Left"

    FontSize="12" FontFamily="Verdana"

    TextWrapping="Wrap" TextAlignment="Left" Padding="2"

           TextDecorations="Underline">

Listing 7

The new output looks like Figure 4.

Figure 4

Background

 

The Background property represents the background color of a TextBlock. Listing 8 sets the Background property of a TextBlock to a LinearGradientBrush. 

<TextBlock.Background>

    <LinearGradientBrush StartPoint="0,0" EndPoint="1,1" >

        <GradientStop Color="Blue" Offset="0.1" />

        <GradientStop Color="Orange" Offset="0.25" />                   

        <GradientStop Color="Green" Offset="0.75" />

        <GradientStop Color="Red" Offset="1.0" />

    </LinearGradientBrush>

</TextBlock.Background>

Listing 7

The code snippet in Listing 8 sets an image as background of a TextBlock.

<TextBlock.Background>

    <ImageBrush ImageSource="Garden.jpg" Opacity="0.6"/>

</TextBlock.Background>

 

Summary

In this article, I discussed how we can create and format a TextBlock control in WPF and C#.  After that we saw how to create a TextBlock control dynamically. Then we saw how to set various properties of a TextBlock such as fonts, Inlines, and text decorations.