proe二次开发：装配添加约束求救

mydear

现在我在装配体里面有一个圆柱体，我现在通过程序将另外一个圆柱体添加进来并进行约束添加，添加进来了，但是我在添加约束的时候老是发生异常，我把代码贴出来大家看看帮帮忙吧。
6 s9 E; u* p' t  r' F! k        Dim model As IpfcModel
2 ~: d, F9 T! D6 n0 m+ y. a        model = session.CurrentModel
        Dim assembly As IpfcAssembly
% B0 B2 S7 f* D1 m3 f' A( D* S        assembly = CType(model, IpfcAssembly)
1 |8 o! L6 K& g2 p. ?9 o3 F
4 W" _1 o9 z) L  O& D1 {        MsgBox(CType(assembly, IpfcSolid).ListFeaturesByType(True, EpfcFeatureType.EpfcFEATTYPE_DATUM_AXIS).Count.ToString())
; D6 m6 e( J0 C/ U9 `        'MsgBox(CType(assembly, IpfcModelItemOwner).ListItems(EpfcModelItemType.EpfcITEM_AXIS).Count.ToString())
! ~' k% I% [) p4 _
% }0 k2 ?+ \3 O6 F& l: g& r) a        Dim models As IpfcModels
7 r0 n( \% }* W! \) e  J        models = session.ListModels()
        Dim asmmodelitemowner As IpfcModelItemOwner
        asmmodelitemowner = CType(models(1), IpfcModelItemOwner)//获取到原先已经添加进来的圆柱作为modelitemowner

8 S2 g" V5 v* _- g+ K% x        Dim compmodelitemowner As IpfcModelItemOwner
        compmodelitemowner = CType(componentModel, IpfcModelItemOwner)//后来添加的圆柱owner
        Dim asmitem As IpfcModelItem
        Dim compitem As IpfcModelItem
4 c& L3 T( i0 k. D. T9 }        Try
7 a2 b6 w; M1 D( x; t$ r* r! P            asmitem = asmmodelitemowner.GetItemById(EpfcModelItemType.EpfcITEM_AXIS, Convert.ToInt32(assemblyitemID))//通过id获取我所选择的圆柱的中心轴。
- w- o* B% M6 p' l8 ~            compitem = compmodelitemowner.GetItemById(EpfcModelItemType.EpfcITEM_AXIS, Convert.ToInt32(componentitemID))//通过id获取我所选择的圆柱的中心轴。
            Dim constrains As IpfcComponentConstraints
            Dim constrain As IpfcComponentConstraint
            constrains = New CpfcComponentConstraints
' R% X& z4 Z& n. p            Dim ids As Cintseq
            Dim path As IpfcComponentPath
  ~* p8 c" A) |7 z* L# m            ids = New Cintseq
            path = (New CMpfcAssembly).CreateComponentPath(assembly, ids)//创建一个path
2 A9 ^0 H! G2 Z. h            Dim asmSelection As IpfcSelection
" `* S- |2 y/ w' \' W            Dim compSelection As IpfcSelection
) b; B' h' X- `, B3 _//通过modelitem创建selection对象，作为下面的reference
" `8 [1 A/ o  |/ Y$ W2 A4 B            asmSelection = (New CMpfcSelect).CreateModelItemSelection(asmitem, Nothing)
            compSelection = (New CMpfcSelect).CreateModelItemSelection(compitem, Nothing)

1 O) V8 D' k5 h; _# ^            constrain = (New CCpfcComponentConstraint).Create(EpfcComponentConstraintType.EpfcASM_CONSTRAINT_ALIGN)
5 z' N% B( d/ n8 l$ l$ x            constrain.ComponentReference = asmSelection
            constrain.ComponentReference = compSelection
, b' q* h8 K( e            'constrain.Offset = 10.0
% g; {' b; }  M/ J            constrains.Insert(constrains.Count, constrain)
5 x6 O% f' U8 _" s1 l            assemblycompfeat.SetConstraints(constrains, path)//执行到这儿的时候发生异常
            assembly.Regenerate(Nothing)
1 Q/ B2 f, }- l- \0 i* `4 o- @( V8 P6 i3 {请大侠过目指点

lzkeane

constrain.ComponentReference = asmSelection
4 b% F7 C  N$ v0 ]/ _2 |            constrain.ComponentReference = compSelection
. ~! }$ V; Z! g- J1 z这里错了