运行程序，发现有上面这种错误，是什么原因啊
错误是：error LNK2019: 无法解析的外部符号 "enum ProErrors __cdecl UsrPartFeatVisFn(struct pro_model_item *,enum ProErrors,class CArray<struct pro_model_item,struct pro_model_item> *)" (?UsrPartFeatVisFn@@YA?AW4ProErrors@@PAUpro_model_item@@W41@PAV?$CArray@Upro_model_item@@U1@@@@Z)，该符号在函数 "void __cdecl UsrGetDimOfSolid(struct sld_part *,class CArray<struct pro_model_item,struct pro_model_item> &)" (?UsrGetDimOfSolid@@YAXPAUsld_part@@AAV?$CArray@Upro_model_item@@U1@@@@Z) 中被引用 错误是：error LNK2019:
错误是：error LNK2019: 无法解析的外部符号 "enum ProErrors __cdecl UsrPartFeatVisFn(struct pro_model_item *,enum ProErrors,class CArray<struct pro_model_item,struct pro_model_item> *)" (?UsrPartFeatVisFn@@YA?AW4ProErrors@@PAUpro_model_item@@W41@PAV?$CArray@Upro_model_item@@U1@@@@Z)，该符号在函数 "void __cdecl UsrGetDimOfSolid(struct sld_part *,class CArray<struct pro_model_item,struct pro_model_item> &)" (?UsrGetDimOfSolid@@YAXPAUsld_part@@AAV?$CArray@Upro_model_item@@U1@@@@Z) 中被引用 错误是：error LNK2019:
