I am not able retrieve product category id form opportunity

Hi,

I am not able retrieve product category id form opportunity

I want get product category id form opportunity .

Please find the following code.

.xbo

element COpportunityID:BusinessTransactionDocumentID;

before save .absl

var  opporItems = Opportunity.Retrieve(this.COpportunityID).Item;

//foreach(var opporItem in opporItems){

//this.ProductList="xxxx";

varopporProduct = opporItems.ItemProduct;

foreach(varproductinopporProduct)

{

1. this.ProductList = product.ProductCategoryHierarchyProductCategoryIDKey.ProductCategoryInternalID+";";

}

Here Productlist is KUT field so I am assigning all the product category id with colon separated by to Productlist .

Please help on this.

Thanks in advanced.

Thanks & Regards,

SRINIVAS BORRA