
出錯提視:'Object reference not set to an instance of an object.'
請問:如何能讓Classrom.Professor的值讀出來
uj5u.com熱心網友回復:
指定的student物體類里沒有professor這個欄位,沒辦法這么用吧uj5u.com熱心網友回復:
那應該怎么寫呢?uj5u.com熱心網友回復:
..不好意思剛才沒仔細看,既然有item.classrom的話應該不是類的問題是你sql寫錯了,這句sql陳述句能運行嗎?好像不行吧
select * from Students as s left join (select ID from Classroms where Professor='Li na') as c on s.ClassId = c.Id
試試這句呢
uj5u.com熱心網友回復:
select * from Students as s left join (select * from Classroms where Professor='Li na') as c on s.ClassId = c.Id
uj5u.com熱心網友回復:
謝謝了。。我用EF的join()寫的。uj5u.com熱心網友回復:
謝謝你的回答。不好意思,剛才沒有分了。。
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