dsLinq.Count() 引发了“System.NullReferenceException”类型的异常
Posted jeremy2001
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DataTable dt = PurchaseArriveInfoBus.GetPurchaseArriveInfo(companyCD, txtArriveNo, txtTitle, txtProvider);
XElement dsXML = ConvertDataTableToXML(dt);
//linq排序
var dsLinq =
(order == "ascending") ?
(from x in dsXML.Descendants("Data")
orderby x.Element(orderBy).Value ascending
select new DataSourceModel()
{
ID = x.Element("ID").Value,
ArriveNo = x.Element("ArriveNo").Value,
Title = x.Element("Title").Value,
ProviderID = x.Element("ProviderName").Value,
Purchaser = x.Element("Purchaser").Value,
ProductNo = x.Element("ProductNo").Value,
ProductName = x.Element("ProductName").Value,
ColorName = x.Element("ColorName").Value,
TotalPrice = x.Element("TotalPrice").Value,
ProductCount = x.Element("ProductCount").Value,
InCount = x.Element("InCount").Value,
DetailID = x.Element("DetailID").Value,
UnitName = x.Element("UnitName").Value,
JiBenCount = x.Element("JiBenCount").Value,
UnitPrice = IsDisplayPrice ? x.Element("UnitPrice").Value : "0.000000"
})
:
(from x in dsXML.Descendants("Data")
orderby x.Element(orderBy).Value descending
select new DataSourceModel()
{
ID = x.Element("ID").Value,
ArriveNo = x.Element("ArriveNo").Value,
Title = x.Element("Title").Value,
ProviderID = x.Element("ProviderName").Value,
Purchaser = x.Element("Purchaser").Value,
ProductNo = x.Element("ProductNo").Value,
ProductName = x.Element("ProductName").Value,
ColorName = x.Element("ColorName").Value,
TotalPrice = x.Element("TotalPrice").Value,
ProductCount = x.Element("ProductCount").Value,
InCount = x.Element("InCount").Value,
DetailID = x.Element("DetailID").Value,
UnitName = x.Element("UnitName").Value,
JiBenCount = x.Element("JiBenCount").Value,
UnitPrice = IsDisplayPrice ? x.Element("UnitPrice").Value : "0.000000"
});
int totalCount = dsLinq.Count();
dsLinq.Count() 引发了“System.NullReferenceException”类型的异常,其中任何字段都不能为null
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