TextSource.GetTextRun(Int32) Metod

public:
 abstract System::Windows::Media::TextFormatting::TextRun ^ GetTextRun(int textSourceCharacterIndex);

public abstract System.Windows.Media.TextFormatting.TextRun GetTextRun(int textSourceCharacterIndex);

abstract member GetTextRun : int -> System.Windows.Media.TextFormatting.TextRun

Public MustOverride Function GetTextRun (textSourceCharacterIndex As Integer) As TextRun

Parametrar

Returer

Ett värde som representerar ett TextRun, eller ett objekt som härletts från TextRun.

Exempel

I följande exempel implementeras en åsidosättning för GetTextRun metoden.

// Retrieve the next formatted text run for the text source.
public override TextRun GetTextRun(int textSourceCharacterIndex)
{
    // Determine whether the text source index is in bounds.
    if (textSourceCharacterIndex < 0)
    {
        throw new ArgumentOutOfRangeException("textSourceCharacterIndex", "Value must be greater than 0.");
    }

    // Determine whether the text source index has exceeded or equaled the text source length.
    if (textSourceCharacterIndex >= _text.Length)
    {
        // Return an end-of-paragraph indicator -- a TextEndOfParagraph object is a special type of text run.
        return new TextEndOfParagraph(1);
    }

    // Create and return a TextCharacters object, which is formatted according to
    // the current layout and rendering properties.
    if (textSourceCharacterIndex < _text.Length)
    {
        // The TextCharacters object is a special type of text run that contains formatted text.
        return new TextCharacters(
           _text,                                       // The text store
           textSourceCharacterIndex,                    // The text store index
           _text.Length - textSourceCharacterIndex,     // The text store length
           new CustomTextRunProperties());              // The layout and rendering properties
    }

    // Return an end-of-paragraph indicator if there is no more text source.
    return new TextEndOfParagraph(1);
}

' Retrieve the next formatted text run for the text source.
Public Overrides Function GetTextRun(ByVal textSourceCharacterIndex As Integer) As TextRun
    ' Determine whether the text source index is in bounds.
    If textSourceCharacterIndex < 0 Then
        Throw New ArgumentOutOfRangeException("textSourceCharacterIndex", "Value must be greater than 0.")
    End If

    ' Determine whether the text source index has exceeded or equaled the text source length.
    If textSourceCharacterIndex >= _text.Length Then
        ' Return an end-of-paragraph indicator -- a TextEndOfParagraph object is a special type of text run.
        Return New TextEndOfParagraph(1)
    End If

    ' Create and return a TextCharacters object, which is formatted according to
    ' the current layout and rendering properties.
    If textSourceCharacterIndex < _text.Length Then
        ' The TextCharacters object is a special type of text run that contains formatted text.
        Return New TextCharacters(_text, textSourceCharacterIndex, _text.Length - textSourceCharacterIndex, New CustomTextRunProperties()) ' The layout and rendering properties -  The text store length -  The text store index -  The text store
    End If

    ' Return an end-of-paragraph indicator if there is no more text source.
    Return New TextEndOfParagraph(1)
End Function

Kommentarer

En textkörning är en sekvens med tecken som delar en enda egenskapsuppsättning. Alla ändringar i formatet, till exempel teckensnittsfamilj, teckensnittsstil, förgrundsfärg, textdekoration eller någon annan formateringseffekt, bryter textkörningen. Klassen TextRun är roten i en typhierarki som representerar flera typer av textinnehåll som bearbetas av TextFormatter. Varje klass som härleds från TextRun representerar en distinkt typ av textinnehåll.