CharacterRange(Int32, Int32) Constructeur

Définition

Espace de noms:

System.Drawing

Assembly:

System.Drawing.Common.dll

Paquet:

System.Drawing.Common v8.0.0

Source:

CharacterRange.cs

Initialise une nouvelle instance de la structure CharacterRange en spécifiant une plage de positions de caractères dans une chaîne.

public:
 CharacterRange(int First, int Length);

public CharacterRange (int First, int Length);

new System.Drawing.CharacterRange : int * int -> System.Drawing.CharacterRange

Public Sub New (First As Integer, Length As Integer)

Paramètres

First

Int32

Position du premier caractère dans la plage. Par exemple, si la valeur de First est 0, la première position de la plage correspond à la position 0 dans la chaîne.

Length

Int32

Nombre de positions dans la plage.

Exemples

L’exemple de code suivant montre comment créer un CharacterRange et l’utiliser pour mettre en surbrillance une partie d’une chaîne. Cet exemple est conçu pour être utilisé avec Windows Forms. Collez l’exemple dans un formulaire et appelez la méthode lors de la HighlightACharacterRange gestion de l’événement du Paint formulaire, en passant e comme PaintEventArgs.

void HighlightACharacterRange( PaintEventArgs^ e )
{
   // Declare the string to draw.
   String^ message = "This is the string to highlight a word in.";

   // Declare the word to highlight.
   String^ searchWord = "string";

   // Create a CharacterRange array with the searchWord 
   // location and length.
   array<CharacterRange>^ temp = {CharacterRange( message->IndexOf( searchWord ), searchWord->Length )};
   array<CharacterRange>^ranges = temp;

   // Construct a StringFormat object.
   StringFormat^ stringFormat1 = gcnew StringFormat;

   // Set the ranges on the StringFormat object.
   stringFormat1->SetMeasurableCharacterRanges( ranges );

   // Declare the font to write the message in.
   System::Drawing::Font^ largeFont = gcnew System::Drawing::Font( FontFamily::GenericSansSerif,16.0F,GraphicsUnit::Pixel );

   // Construct a new Rectangle.
   Rectangle displayRectangle = Rectangle(20,20,200,100);

   // Convert the Rectangle to a RectangleF.
   RectangleF displayRectangleF = displayRectangle;

   // Get the Region to highlight by calling the 
   // MeasureCharacterRanges method.
   array<System::Drawing::Region^>^charRegion = e->Graphics->MeasureCharacterRanges( message, largeFont, displayRectangleF, stringFormat1 );

   // Draw the message string on the form.
   e->Graphics->DrawString( message, largeFont, Brushes::Blue, displayRectangleF );

   // Fill in the region using a semi-transparent color.
   e->Graphics->FillRegion( gcnew SolidBrush( Color::FromArgb( 50, Color::Fuchsia ) ), charRegion[ 0 ] );
   delete largeFont;
}

private void HighlightACharacterRange(PaintEventArgs e)
{

    // Declare the string to draw.
    string message = "This is the string to highlight a word in.";

    // Declare the word to highlight.
    string searchWord = "string";

    // Create a CharacterRange array with the searchWord 
    // location and length.
    CharacterRange[] ranges = 
        new CharacterRange[]{new CharacterRange
        (message.IndexOf(searchWord), searchWord.Length)};

    // Construct a StringFormat object.
    StringFormat stringFormat1 = new StringFormat();

    // Set the ranges on the StringFormat object.
    stringFormat1.SetMeasurableCharacterRanges(ranges);

    // Declare the font to write the message in.
    Font largeFont = new Font(FontFamily.GenericSansSerif, 16.0F,
        GraphicsUnit.Pixel);

    // Construct a new Rectangle.
    Rectangle displayRectangle = new Rectangle(20, 20, 200, 100);

    // Convert the Rectangle to a RectangleF.
    RectangleF displayRectangleF = (RectangleF)displayRectangle;

    // Get the Region to highlight by calling the 
    // MeasureCharacterRanges method.
    Region[] charRegion = e.Graphics.MeasureCharacterRanges(message, 
        largeFont, displayRectangleF, stringFormat1);

    // Draw the message string on the form.
    e.Graphics.DrawString(message, largeFont, Brushes.Blue, 
        displayRectangleF);

    // Fill in the region using a semi-transparent color.
    e.Graphics.FillRegion(new SolidBrush(Color.FromArgb(50, Color.Fuchsia)), 
        charRegion[0]);

    largeFont.Dispose();
}

Private Sub HighlightACharacterRange(ByVal e As PaintEventArgs)

    ' Declare the string to draw.
    Dim message As String = _
        "This is the string to highlight a word in."

    ' Declare the word to highlight.
    Dim searchWord As String = "string"

    ' Create a CharacterRange array with the searchWord 
    ' location and length.
    Dim ranges() As CharacterRange = _
        New CharacterRange() _
            {New CharacterRange(message.IndexOf(searchWord), _
            searchWord.Length)}

    ' Construct a StringFormat object.
    Dim stringFormat1 As New StringFormat

    ' Set the ranges on the StringFormat object.
    stringFormat1.SetMeasurableCharacterRanges(ranges)

    ' Declare the font to write the message in.
    Dim largeFont As Font = New Font(FontFamily.GenericSansSerif, _
        16.0F, GraphicsUnit.Pixel)

    ' Construct a new Rectangle.
    Dim displayRectangle As New Rectangle(20, 20, 200, 100)

    ' Convert the Rectangle to a RectangleF.
    Dim displayRectangleF As RectangleF = _
        RectangleF.op_Implicit(displayRectangle)

    ' Get the Region to highlight by calling the 
    ' MeasureCharacterRanges method.
    Dim charRegion() As Region = _
        e.Graphics.MeasureCharacterRanges(message, _
        largeFont, displayRectangleF, stringFormat1)

    ' Draw the message string on the form.
    e.Graphics.DrawString(message, largeFont, Brushes.Blue, _
        displayRectangleF)

    ' Fill in the region using a semi-transparent color.
    e.Graphics.FillRegion(New SolidBrush(Color.FromArgb(50, _
        Color.Fuchsia)), charRegion(0))

End Sub