情景：
我自定义开发了一张单据，单据上物料，物料分组编码，分组名称，现在想通过物料 获取到 物料分组编码 和分组名称，不知道怎么写？
List
goodsFields.Add(new SelectorItemInfo("FMATERIALID"));
goodsFields.Add(new SelectorItemInfo("FName"));
goodsFields.Add(new SelectorItemInfo("FNumber"));
OQLFilter filter=null;
DynamicObject[] goods = BusinessDataServiceHelper.Load(this.Context, "BD_MATERIAL", goodsFields, filter);
foreach (DynamicObject doItem in goods)
{
FormMetadata meta = MetaDataServiceHelper.Load(this.Context, "PBVB_slyp_materialgroup", true) as FormMetadata;
DynamicObject obj = new DynamicObject(meta.BusinessInfo.GetDynamicObjectType());
obj["CreateDate"] = DateTime.Now;
obj["FModifyDate"] = DateTime.Now;
obj["F_PBVB_material_id"] =doItem["Id"].ToString();
obj["CreatorId_id"] = this.Context.UserId;
obj["ModifierId_id"] = this.Context.UserId;
obj["DocumentStatus"] = "A";
obj["ForbidStatus"] = "A";
obj["F_PBVB_groupname"] = 分组名称; //这里需要解决
obj["F_PBVB_materialfroup"] = 分组编码; //这里需要解决
BusinessDataServiceHelper.Save(this.Context, obj);
}
请高手指点啊！