RectangleF.Union(RectangleF, RectangleF) 方法

定義

命名空間:

System.Drawing

組件:

netstandard.dll, System.Drawing.Primitives.dll

來源:

RectangleF.cs

創造最小的第三個矩形，能包含兩個形成聯集的矩形。

public:
 static System::Drawing::RectangleF Union(System::Drawing::RectangleF a, System::Drawing::RectangleF b);

public static System.Drawing.RectangleF Union(System.Drawing.RectangleF a, System.Drawing.RectangleF b);

static member Union : System.Drawing.RectangleF * System.Drawing.RectangleF -> System.Drawing.RectangleF

Public Shared Function Union (a As RectangleF, b As RectangleF) As RectangleF

參數

a

RectangleF

一個矩形到聯合。

b

RectangleF

一個矩形到聯合。

傳回

RectangleF

第三 RectangleF 個結構包含形成聯集的兩個矩形。

範例

此範例設計用於 Windows Forms，且需要 PaintEventArgs e，一個 OnPaint 事件物件。 程式碼會產生兩個 RectangleF s，並以黑紅相間的畫面呈現。 請注意，為了繪製目的，必須將它們轉換成 Rectangle s。 接著程式碼會用這個RectangleF方法產生第三Union個，轉換成 Rectangle，然後用藍色畫到螢幕上。 請注意第三個（藍色）矩形是能同時包含另外兩個矩形的最小矩形：

public:
   void RectangleFUnionExample( PaintEventArgs^ e )
   {
      // Create two rectangles and draw them to the screen.
      RectangleF firstRectangleF = RectangleF(0,0,75,50);
      RectangleF secondRectangleF = RectangleF(100,100,20,20);

      // Convert the RectangleF structures to Rectangle structures and draw them to the
      // screen.
      Rectangle firstRect = Rectangle::Truncate( firstRectangleF );
      Rectangle secondRect = Rectangle::Truncate( secondRectangleF );
      e->Graphics->DrawRectangle( Pens::Black, firstRect );
      e->Graphics->DrawRectangle( Pens::Red, secondRect );

      // Get the union rectangle.
      RectangleF unionRectangleF = RectangleF::Union( firstRectangleF, secondRectangleF );

      // Draw the unionRectangleF to the screen.
      Rectangle unionRect = Rectangle::Truncate( unionRectangleF );
      e->Graphics->DrawRectangle( Pens::Blue, unionRect );
   }

public void RectangleFUnionExample(PaintEventArgs e)
{
             
    // Create two rectangles and draw them to the screen.
    RectangleF firstRectangleF = new RectangleF(0, 0, 75, 50);
    RectangleF secondRectangleF = new RectangleF(100, 100, 20, 20);
             
    // Convert the RectangleF structures to Rectangle structures and draw them to the
             
    // screen.
    Rectangle firstRect = Rectangle.Truncate(firstRectangleF);
    Rectangle secondRect = Rectangle.Truncate(secondRectangleF);
    e.Graphics.DrawRectangle(Pens.Black, firstRect);
    e.Graphics.DrawRectangle(Pens.Red, secondRect);
             
    // Get the union rectangle.
    RectangleF unionRectangleF = RectangleF.Union(firstRectangleF,
        secondRectangleF);
             
    // Draw the unionRectangleF to the screen.
    Rectangle unionRect = Rectangle.Truncate(unionRectangleF);
    e.Graphics.DrawRectangle(Pens.Blue, unionRect);
}

Public Sub RectangleFUnionExample(ByVal e As PaintEventArgs)

    ' Create two rectangles and draw them to the screen.
    Dim firstRectangleF As New RectangleF(0, 0, 75, 50)
    Dim secondRectangleF As New RectangleF(100, 100, 20, 20)

    ' Convert the RectangleF structures to Rectangle structures and

    ' draw them to the screen.
    Dim firstRect As Rectangle = Rectangle.Truncate(firstRectangleF)
    Dim secondRect As Rectangle = Rectangle.Truncate(secondRectangleF)
    e.Graphics.DrawRectangle(Pens.Black, firstRect)
    e.Graphics.DrawRectangle(Pens.Red, secondRect)

    ' Get the union rectangle.
    Dim unionRectangleF As RectangleF = _
    RectangleF.Union(firstRectangleF, secondRectangleF)

    ' Draw the unionRectangleF to the screen.
    Dim unionRect As Rectangle = Rectangle.Truncate(unionRectangleF)
    e.Graphics.DrawRectangle(Pens.Blue, unionRect)
End Sub

備註

當其中一個矩形為空，表示所有值皆為零時，方法 Union 會回傳一個起始點為 （0， 0） 的矩形，並標示該矩形的高度與寬度。 例如，若有兩個矩形 A = （0， 0; 0， 0） 與 B = （1， 1; 2， 2），則 A 與 B 的聯集為 （0， 0; 2， 2）。