[编程申请]：求助

flydyt

在VB中，如何取得一个任意多边形内的点、线和跟这个多边形相交的线，谢谢

efan2000

用IntersectWith函数。

2. 
   
3.   [FONT=courier new]
   
4. Sub Example_IntersectWith()
   
5. 
   
6.     ' 创建直线
   
7.     Dim lineObj As AcadLine
   
8.     Dim startPt(0 To 2) As Double
   
9.     Dim endPt(0 To 2) As Double
   
10.     startPt(0) = 1: startPt(1) = 1: startPt(2) = 0
    
11.     endPt(0) = 5: endPt(1) = 5: endPt(2) = 0
    
12. 
    
13.     Set lineObj = ThisDrawing.ModelSpace.AddLine(startPt, endPt)
    
14.         
    
15.     ' 创建圆
    
16.     Dim circleObj As AcadCircle
    
17.     Dim centerPt(0 To 2) As Double
    
18.     Dim radius As Double
    
19.     centerPt(0) = 3: centerPt(1) = 3: centerPt(2) = 0
    
20.     radius = 1
    
21.     Set circleObj = ThisDrawing.ModelSpace.AddCircle(centerPt, radius)
    
22. 
    
23.       
    
24.     ' 判断直线和圆是否有交点及交点坐标，返回值为空表示不相交，否则返回值就是所有交点的坐标。
    
25.     Dim intPoints As Variant
    
26.     intPoints = lineObj.IntersectWith(circleObj, acExtendNone)
    
27.    
    
28.     ' Print all the intersection points
    
29.     Dim I As Integer, j As Integer, k As Integer
    
30.     Dim str As String
    
31.     If VarType(intPoints) <> vbEmpty Then
    
32. 
    
33.         For I = LBound(intPoints) To UBound(intPoints)
    
34.             str = "交点[" & k & "] is: " & intPoints(j) & "," & intPoints(j + 1) & "," & intPoints(j + 2)
    
35.             MsgBox str, , "相交示例"
    
36.             str = ""
    
37.             I = I + 2
    
38.             j = j + 3
    
39.             k = k + 1
    
40. 
    
41.         Next
    
42.     End If
    
43. End Sub
    
44.   [/FONT]
    

<br />   [FONT=courier new]<br /> Sub Example_IntersectWith()<br /> <br />     ' 创建直线<br />     Dim lineObj As AcadLine<br />     Dim startPt(0 To 2) As Double<br />     Dim endPt(0 To 2) As Double<br />     startPt(0) = 1: startPt(1) = 1: startPt(2) = 0<br />     endPt(0) = 5: endPt(1) = 5: endPt(2) = 0<br /> <br />     Set lineObj = ThisDrawing.ModelSpace.AddLine(startPt, endPt)<br />         <br />     ' 创建圆<br />     Dim circleObj As AcadCircle<br />     Dim centerPt(0 To 2) As Double<br />     Dim radius As Double<br />     centerPt(0) = 3: centerPt(1) = 3: centerPt(2) = 0<br />     radius = 1<br />     Set circleObj = ThisDrawing.ModelSpace.AddCircle(centerPt, radius)<br /> <br />       <br />     ' 判断直线和圆是否有交点及交点坐标，返回值为空表示不相交，否则返回值就是所有交点的坐标。<br />     Dim intPoints As Variant<br />     intPoints = lineObj.IntersectWith(circleObj, acExtendNone)<br />     <br />     ' Print all the intersection points<br />     Dim I As Integer, j As Integer, k As Integer<br />     Dim str As String<br />     If VarType(intPoints) <> vbEmpty Then<br /> <br />         For I = LBound(intPoints) To UBound(intPoints)<br />             str = "交点[" & k & "] is: " & intPoints(j) & "," & intPoints(j + 1) & "," & intPoints(j + 2)<br />             MsgBox str, , "相交示例"<br />             str = ""<br />             I = I + 2<br />             j = j + 3<br />             k = k + 1<br /> <br />         Next<br />     End If<br /> End Sub<br />   [/FONT]<br />