GP工具编辑TIN的问题（C#代码如下，是哪里出现了问题呢）

Geoprocessor GP = new Geoprocessor();
ESRI.ArcGIS.Analyst3DTools.EditTin pEditTIN = new EditTin();
pEditTIN.in_tin = frmMain.WorkFile + "\\" + "TIN";
pEditTIN.in_features = pFeatureLayer;
GP.Execute(pEditTIN, null);