网络路径分析 ITraceFlowSolver 接口问题

<P>需要完成路径分析功能,要用到ITraceFlowSolver接口中FindPath方法,</P>
<P>代码:</P>
<P>ITraceFlowSolver pTraceFlowSolver;</P>
<P>pTraceFlowSolver=(ITraceFlowSolver)new ESRI.ArcGIS.NetworkAnalysis.TraceFlowSolverClass();</P>
<P> INetSolver pNetSolver;</P>
<P>pNetSolver=(INetSolver)pTraceFlowSolver;<BR>    if(pNetSolver==null) return;<BR>    pNetwork=pGeometricNetwork.Network;<BR>    pNetSolver.SourceNetwork=pNetwork;</P>
<P> //设置网络起始边线元素<BR>    pTraceFlowSolver.PutEdgeOrigins(icount-iPointNum,ref pEdgeFlag[0]);</P>
<P>执行到这一句就报 参数不正确 的错误.仔细看了ITraceFlowSolver 接口,觉得参数是这样设置的,不知道哪里出问题了</P>
<P>希望哪位高手帮我看一下!</P>