var query1 = from a in inputDataRecords
from b in employeeDataRecords
.Where(badgeNumber => a.Responsi == badgeNumber.Badge)
.Where(badgeNumber => a.Auth == badgeNumber.Badge)
.Where(badgeNumber => a.ByN == badgeNumber.Badge)
.DefaultIfEmpty()
select new {a,
responsibleName = b.EmployeeName,
authName = b.EmployeeName,
createName = b.EmployeeName};
給我一個錯誤:對象引用未設置爲對象的實例。 我知道這是因爲我沒有參考b。LINQ查詢中的對象引用錯誤
但改變選擇:
select new {a, b,
responsibleName = b.EmployeeName,
authName = b.EmployeeName,
createName = b.EmployeeName};
沒有幫助。快速查詢query1顯示b爲空。
b如何與a? – 2014-10-01 18:51:41
'.DefaultIfEmpty()'如果它不符合你的標準條件,會導致'b'爲空。 – jrummell 2014-10-01 18:53:05
@Allan - a和b都有一個badgeNumber的公共字段 – KTLind 2014-10-01 19:07:39