Question

当我的客户编号都是数字时，我有一段代码可以使用。因此，现在已经添加了alpha版本的客户编号，我得到了＆＃34; nvarchar值的转换＆＃39; 4000545398＆＃39;溢出了一个int列。超出最大整数值＆＃34;我知道的错误超过了210万等... 我的问题在于，数字4000545398是表shipper_sii [a nvarchar（10）]的第一个记录中的批号。

我的表格中的列如下......

custaddr - name (nvarchar (60)), cust_num (nvarchar(7))
co - cust_num (nvarchar(7)), co_num (nvarchar(10))
shipper_sii - co_num (nvarchar(10)), lot (nvarchar(15))

我的声明是......

 Dim Carton1 As String
 Dim dbCustName As String
 Dim dbCustNum As String

有人为我修好了吗？我在这里摸不着头脑...... 我很确定它在我的加入中，但我很难过......

' Get Customer Name

Using connObj2 As New SqlClient.SqlConnection("server=Server;database=App;uid=sa;pwd=password;")
  Using cmdObj2 As New SqlClient.SqlCommand("SELECT c2.name, c2.cust_num from custaddr as c2 INNER JOIN co as c1 ON (c2.cust_num = c1.cust_num) INNER JOIN shipper_sii as s1 on (c1.co_num = s1.co_num) WHERE lot = " & Carton1, connObj2)
    connObj2.Open()
    Using readerObj2 As SqlClient.SqlDataReader = cmdObj2.ExecuteReader
        'This will loop through all returned records 
        While readerObj2.Read

            dbCustNum = readerObj2("cust_num").ToString
            dbCustName = readerObj2("name").ToString
            'handle returned value before next loop here

        End While
    End Using
    connObj2.Close()
  End Using
End Using

我的错误弹出了＆＃34;而readerObj2.Read＆＃34;。

Answer 1

您应该使用参数化查询来避免此类错误和Sql Injection问题

Dim cmdText = "SELECT c2.name, c2.cust_num from custaddr as c2 " & _
                "INNER JOIN co as c1 ON (c2.cust_num = c1.cust_num)  " & _
                "INNER JOIN shipper_sii as s1 on (c1.co_num = s1.co_num)  " & _
                "WHERE lot = @car"
Using cmdObj2 As New SqlClient.SqlCommand(cmdText, connObj2)
     cmdObj2.Parameters.AddWithValue("@car",  Carton1)
   .....

此处lot是一个NVarChar字段，因此，在字符串连接中，这需要Carton1变量周围的引号，但使用参数化查询可以避免该问题。

Nvarchar转换为整数错误...没有使用整数列时

1 个答案: