[求助]怎样修改cad的扩展数据

laoxie_198

图元已经有扩展数据了，想重新修改它怎么处理呢？

fjfhgdwfn

<pre class="Code">Sub Example_SetXdata()
    ' This example creates a line and attaches extended data to that line.
   
    ' Create the line
    Dim lineObj As AcadLine
    Dim startPt(0 To 2) As Double, endPt(0 To 2) As Double
    startPt(0) = 1#: startPt(1) = 1#: startPt(2) = 0#
    endPt(0) = 5#: endPt(1) = 5#: endPt(2) = 0#
    Set lineObj = ThisDrawing.ModelSpace.AddLine(startPt, endPt)
    ZoomAll

    ' Initialize all the xdata values. Note that first data in the list should be
    ' application name and first datatype code should be 1001
    Dim DataType(0 To 9) As Integer
    Dim Data(0 To 9) As Variant
    Dim reals3(0 To 2) As Double
    Dim worldPos(0 To 2) As Double
   
    DataType(0) = 1001: Data(0) = "Test_Application"
    DataType(1) = 1000: Data(1) = "This is a test for xdata"

    DataType(2) = 1003: Data(2) = "0"                   ' layer
    DataType(3) = 1040: Data(3) = 1.23479137438413E+40  ' real
    DataType(4) = 1041: Data(4) = 1237324938            ' distance
    DataType(5) = 1070: Data(5) = 32767                 ' 16 bit Integer
    DataType(6) = 1071: Data(6) = 32767                 ' 32 bit Integer
    DataType(7) = 1042: Data(7) = 10                    ' scaleFactor

    reals3(0) = -2.95: reals3(1) = 100: reals3(2) = -20
    DataType(8) = 1010: Data(8) = reals3                ' real
   
    worldPos(0) = 4: worldPos(1) = 400.99999999: worldPos(2) = 2.798989
    DataType(9) = 1011: Data(9) = worldPos              ' world space position
   
    ' Attach the xdata to the line
    lineObj.SetXData DataType, Data
   
    ' Return the xdata for the line
    Dim xdataOut As Variant
    Dim xtypeOut As Variant
    lineObj.GetXData "", xtypeOut, xdataOut
   
End Sub</pre>