asp.net - SqlCommand 占位符参数 : "Incorrect syntax near ' ?'" and "Must declare the scalar variable @param"?

Question

我正在为我们公司开发网络 map 应用程序内部网。我正在 map 上创建一个“添加多边形”功能。我使用 AspMap、VB.NET 和 SQL Server。当用户单击按钮以从 Web 表单输入数据属性添加新记录时，发生错误Incorrect syntax near '?'。

我的代码是:

Private Sub AddNewShape(ByVal checklist_id As String, ByVal type As String, ByVal shape As AspMap.Shape, ByVal address_area As String, ByVal dmz As String, ByVal customerid As String, ByVal source As String, ByVal area As String, ByVal instalatur As String, ByVal developer As String, ByVal data_received As DateTime, ByVal doc_data As DateTime, ByVal datereport As DateTime, ByVal remark As String)
    Dim tableName As String

    Select Case shape.ShapeType
        Case AspMap.ShapeType.Line
            tableName = "lines"
        Case AspMap.ShapeType.Polygon
            tableName = "sambungan_baru"
        Case Else
            Return
    End Select

    Dim conn As SqlConnection = GetDbConnection()
    Dim sql As String = "INSERT INTO " & tableName & " (CHECKLIST_ID, TYPE, SHAPEDATA, ADDRESS_AREA, DMZ, CUSTOMERID, SOURCE, AREA, INSTALATUR, DEVELOPER, DATA_RECEIVED, DOC_DATA, DATA_SENT, REMARK) VALUES (?,?,?,?,?,?,?,?,?,?,?,?,?,?)"

    Dim cmd As SqlCommand = New SqlCommand(sql, conn)
    cmd.Parameters.AddWithValue("CHECKLIST_ID", checklist_id)
    cmd.Parameters.AddWithValue("TYPE", type)
    cmd.Parameters.AddWithValue("SHAPEDATA", shape.ShapeData)
    cmd.Parameters.AddWithValue("ADDRESS_AREA", address_area)
    cmd.Parameters.AddWithValue("DMZ", dmz)
    cmd.Parameters.AddWithValue("CUSTOMERID", customerid)
    cmd.Parameters.AddWithValue("SOURCE", source)
    cmd.Parameters.AddWithValue("AREA", area)
    cmd.Parameters.AddWithValue("INSTALATUR", instalatur)
    cmd.Parameters.AddWithValue("DEVELOPER", developer)
    cmd.Parameters.AddWithValue("DATA_RECEIVED", data_received)
    cmd.Parameters.AddWithValue("DOC_DATA", doc_data)
    cmd.Parameters.AddWithValue("DATA_SENT", datereport)
    cmd.Parameters.AddWithValue("REMARK", remark)

    cmd.ExecuteNonQuery()
    conn.Close()

    ReloadShapesDatabase()
End Sub

我改变了这个:

Dim sql As String = "INSERT INTO " & tableName & " (CHECKLIST_ID, TYPE, SHAPEDATA, ADDRESS_AREA, DMZ, CUSTOMERID, SOURCE, AREA, INSTALATUR, DEVELOPER, DATA_RECEIVED, DOC_DATA, DATA_SENT, REMARK) VALUES *(?,?,?,?,?,?,?,?,?,?,?,?,?,?)

为此:

Dim sql As String = "INSERT INTO " & tableName & " (CHECKLIST_ID, TYPE, SHAPEDATA, ADDRESS_AREA, MZ, CUSTOMERID, SOURCE, AREA, INSTALATUR, DEVELOPER, DATA_RECEIVED, DOC_DATA, DATA_SENT, REMARK)(@checklist_id, @type, @shapedata, @address_area, @dmz, @conection, @source, @area, @instalatur, @developer, @data_received, @doc_data, data_sent, @remark)"

然后我遇到了警告:必须声明标量变量“@conection”。有人能帮我吗？

Answer 1

您混淆了 SQL 查询中两种不同样式的参数。 ODBC 语法使用简单的占位符“?”每个参数的字符，并按照您将它们添加到参数集合的相同顺序替换参数。对于 OdbcCommand，您为参数指定的名称将被忽略，只有它们的顺序很重要。

对于SqlCommand，参数名是有意义的；当命令执行时，它将通过一个 SQL 存储过程运行，该过程获取参数名称和值的列表并将它们替换到 T-SQL 查询中。在这种情况下，您向查询添加参数的顺序并不重要，但您需要确保名称正确(包括“@”前缀。)

使用带参数的 SqlCommand 的正确方法如下:

// The SQL Query: Note the use of named parameters of the form
// @ParameterName1, @ParameterName2, etc.
Dim sql As String = "INSERT INTO " & tableName & _
"    (CHECKLIST_ID, TYPE, SHAPEDATA ) " & _
"VALUES " & _
"    (@ChecklistId, @Type, @ShapeData )"

// The Parameter List. Note that the Parameter name must exactly match
// what you use in the query:
Dim cmd As SqlCommand = New SqlCommand(sql, conn)
cmd.Parameters.AddWithValue("@CheckListId", checklist_id)
cmd.Parameters.AddWithValue("@Type", type)
cmd.Parameters.AddWithValue("@ShapeData", shape.ShapeData)

cmd.ExecuteNonQuery()