VB编程操作AutoCAD半径和直径型尺寸标注

半径或直径型尺寸标注用来标注圆或圆弧，半径或直径型标注的类型与圆或圆弧的大小，TextPosition属性有关也与尺寸标注系统变量DIMUPT、DIMTOFL、DIMTIH、DIMTOH、DIMJUST、DIMTAD的值有关，系统变量用GetVariable和SetVariable方法返回。

创建半径型尺寸标注对象用AddDimRadial方法，语法格式如下。

RetVal=object.AddDimRadial(Center,ChordPoint,LeaderLength)

创建直径型尺寸标注对象用AddDimRadial方法，语法格式如下。

RetVal=object.AddDimDiametric(ChordPoint,FarChordPoint,LeaderLength)

下面的代码创建一个直径型尺寸标注。

Private Sub Command1_Click()
    Dim circleobj As AcadCircle
    Dim centerpoint(0 To 2) As Double
    Dim radius As Double
    centerpoint(0) = 10#: centerpoint(1) = 5#: centerpoint(2) = 0#
    radius = 5
    Set circleobj = acadapp.ActiveDocument.ModelSpace.AddCircle(centerpoint, radius)
    Dim dimobj As AcadDimDiametric
    Dim chordpoint(0 To 2) As Double
    Dim farchordpoint(0 To 2) As Double
    Dim leaderlength As Double
    chordpoint(0) = 15#: chordpoint(1) = 5#: chordpoint(2) = 0
    farchordpoint(0) = 5#: farchordpoint(1) = 5#: farchordpoint(2) = 0#
    leaderlength = 1#
    Set dimobj = acadapp.ActiveDocument.ModelSpace.AddDimDiametric(chordpoint, farchordpoint, leaderlength)
    ZoomExtents
End Sub