LINQ查詢拋出“從字符串轉換為類型” Long”無效”錯誤

Question

我對以下LINQ查詢有問題，該查詢在帖子標題中引發了異常：

Dim test = From Match In _
           (From Load In dtContacts _
           Group Join Siebel In dtSiebel _
           On Load("Email") Equals Siebel("EMAIL_ADDRESS") _
           Into g = Group _
           From LoadResults In g.DefaultIfEmpty _
           Where Not LoadResults Is Nothing _
           Select Email_Address = Load.Field(Of String)("Email"), _
                  Load_Account_Number = Load.Field(Of String)("AccountNum")) _
           Group Join Acct In dtSiebel _
           On Match.Email_Address Equals Acct("EMAIL_ADDRESS") _
                And Not Match.Load_Account_Number Equals Acct("ACCOUNT_NUMBER") _
           Into h = Group _
           From MatchResults In h.DefaultIfEmpty _
           Where Not MatchResults Is Nothing _
           Select Contact_Row_ID = MatchResults.Field(Of String)("CONTACT_ROW_ID"), _
                  Match.Email_Address, _
                  Match.Load_Account_Number, _
                  Account_Num_Chk = MatchResults.Field(Of String)("ACCOUNT_NUMBER")

罪魁禍首是這條線：

And Not Match.Load_Account_Number Equals Acct("ACCOUNT_NUMBER")

對我而言，沒有意義的是，如果刪除了“ Not”子句（用於另一種用例），而其余的查詢保持不變，那么我會得到預期的結果而沒有任何異常。 這里有什么問題？

Answer 1

你可以試試

And Also Not Match.Load_Account_Number Equals Acct("ACCOUNT_NUMBER")