與LINQ查詢工作我收到錯誤LINQ的,如何檢查是否字段的值爲null
System.NullReferenceException同時:未設置爲對象的實例 對象引用。
var db = from d in DepartmentBLL.GetDepartmentList()
join b in BudgetMasterBLL.GetBudgetMasterList()
on d.Departmentid equals b.Departmentid into leftJoin
from results in leftJoin.DefaultIfEmpty()
select new
{
Name = d.Name,
Create = results.Budgetmasterid == null ? "null": "value", //ERROR HERE
CreateURL = "frmBudgetInitial.aspx?departmentid=" + d.Departmentid.ToString() + "&departmentcategoryid=" + d.Departmentcategoryid.ToString()
};
我發現論壇上一些幫助,但並沒有解決我的問題,請指教。謝謝,
首次檢查結果使用results.Budgetmasterid – DotNetUser 2012-02-08 13:30:50
由於results.Budgetmasterid是之前爲null字符串值,你不應該檢查String.Empty而不是null? – 2012-02-08 13:37:15