vb.net导出cad所有多段线顶点到txt

好的，您可以使用以下代码实现将CAD中所有多段线的顶点导出到txt文件中：

Public Sub ExportPolylineVerticesToTxt()
    Dim doc As Document = Application.DocumentManager.MdiActiveDocument
    Dim db As Database = doc.Database
    Dim ed As Editor = doc.Editor

    ' 获取选择集中的所有多段线
    Dim psrOpts As New PromptSelectionOptions()
    psrOpts.MessageForAdding = "选择多段线："
    Dim psrRes As PromptSelectionResult = ed.GetSelection(psrOpts)
    If psrRes.Status <> PromptStatus.OK Then
        ed.WriteMessage("未选择多段线！")
        Return
    End If

    Dim selSet As SelectionSet = psrRes.Value
    Dim acTrans As Transaction = db.TransactionManager.StartTransaction()
    Using acTrans

        ' 创建用于写入txt文件的流
        Dim filename As String = "PolylineVertices.txt"
        Dim path As String = "C:\PolylineVertices\"
        If Not IO.Directory.Exists(path) Then
            IO.Directory.CreateDirectory(path)
        End If

        Dim sw As New IO.StreamWriter(path & filename)

        ' 获取每个多段线的顶点并写入txt文件中
        For Each selObjId As SelectedObject In selSet
            Dim pline As Polyline = TryCast(acTrans.GetObject(selObjId.ObjectId, OpenMode.ForRead), Polyline)
            If pline IsNot Nothing Then
                For i As Integer = 0 To pline.NumberOfVertices - 1
                    Dim vertex As Point3d = pline.GetPoint3dAt(i)
                    sw.WriteLine("X: " & vertex.X & " Y: " & vertex.Y & " Z: " & vertex.Z)
                Next
            End If
        Next

        sw.Close()

        acTrans.Commit()
    End Using

    ed.WriteMessage("多段线的顶点已导出到txt文件中！")
End Sub

您可以将此代码添加到VB.NET项目中，并在AutoCAD中使用NETLOAD命令将其加载到AutoCAD中。然后，您可以使用命令名来调用此方法，如下所示：

NETLOAD
"C:\YourVBProjectPath\YourVBProjectName.dll"
ExportPolylineVerticesToTxt

当您运行此命令时，它将提示您选择多段线，然后将多段线的顶点导出到txt文件中。 您可以在C:\PolylineVertices\路径下找到名为PolylineVertices.txt的文件，其中包含多段线的所有顶点。