列表插件中如何取到勾选到的每个单据的对象？

case "TBSPLITAPPROVE":
String[] Ids = this.ListView.SelectedRowsInfo.GetPrimaryKeyValues();
for (int i = 0; i < Ids.Length; i++)
{
DynamicObject bill = null;
{
string sfilter = string.Format("FID = {0} ", Ids[i]);
OQLFilter filter = OQLFilter.CreateHeadEntityFilter(sfilter);
bill = BusinessDataServiceHelper.Load(this.Context, "7278632b-968d-42e8-9d8a-4ec86ea81743", null, filter).FirstOrDefault();
}

我用这样的方式却报错说：在运行时不允许加载标识为“7278632b-968d-42e8-9d8a-4ec86ea81743”的业务对象。

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