CharacterRange(Int32, Int32) 构造函数

定义

命名空间:

System.Drawing

程序集:

System.Drawing.Common.dll

包:

System.Drawing.Common v8.0.0

Source:

CharacterRange.cs

指定字符串内字符位置的范围，初始化 CharacterRange 结构的新实例。

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)

参数

First

Int32

此范围内第一个字符的位置。 例如，如果 First 设置为 0，那么此范围的第一个位置是字符串中的位置 0。

Length

Int32

此范围内的位置数。

示例

下面的代码示例演示如何创建 CharacterRange 并使用它突出显示字符串的一部分。 此示例旨在与 Windows 窗体 一起使用。 将示例粘贴到窗体中， HighlightACharacterRange 并在处理窗体的 Paint 事件时调用 方法，作为 ePaintEventArgs传递。

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