sql-server - SQL Server 到 VB.Net IF EXISTS 需要返回任何内容，但不返回

Question

我有这个:

IF EXISTS 
    (SELECT 1
    FROM User_Passwords
    WHERE up_Password = @CurrentPassword)
    PRINT 'Bad Password'
    --RETURN TRUE
ELSE

根据我遇到的情况，我需要 SP 返回一些内容，1 或 0，或者 string/varchar，这样我就可以在 VB 端做一些工作。但截至目前，它不会返回任何内容，除非我没有正确调用它。这是VB代码:

Public Function UpdatePasswords()

    Dim objCommand As New SqlCommand("Update_Passwords", DatabaseInterface_.Connection)
    objCommand.CommandType = CommandType.StoredProcedure
    objCommand.Parameters.AddWithValue("@ua_pk", ua_pk_)
    objCommand.Parameters.Add(New SqlParameter With {.ParameterName = "@ResetDaysAmount", .SqlDbType = SqlDbType.Int, .Value = Company.GetSetting("PasswordExpireDays", SettingMisc.ReturnDataType.Integer_)})
    objCommand.Parameters.Add(New SqlParameter With {.ParameterName = "@AllowedNumberOfPasswords", .SqlDbType = SqlDbType.Int, .Value = Company.GetSetting("NumberOfPasswords", SettingMisc.ReturnDataType.Integer_)})
    objCommand.Parameters.Add(New SqlParameter With {.ParameterName = "@CurrentPasswordDate", .SqlDbType = SqlDbType.Date, .Value = ua_PasswordDate_})
    objCommand.Parameters.Add(New SqlParameter With {.ParameterName = "@CurrentPassword", .SqlDbType = SqlDbType.VarChar, .Value = ua_Password_})

    If objCommand.ExecuteScalar.ToString() = "Bad Password" Or 1 Then
        Return True
    Else
        Return False
    End If

End Function

Answer 1

您应该使用 SELECT 语句将某些内容返回到代码中

IF EXISTS (SELECT 1 FROM User_Passwords WHERE up_Password = @CurrentPassword)
    SELECT 1
ELSE
    SELECT 0

然后你的代码是

Dim result = Convert.ToInt32(objCommand.ExecuteScalar())
Return If(result = 1, True, False)