Question

我正在尝试根据查询字符串动态更改SQLDataAdapter中的查询。我尝试将其作为参数传递，但这不起作用。还有其他建议吗？

现在我有：

    Dim conn As Data.SqlClient.SqlConnection = New Data.SqlClient.SqlConnection(WebConfigurationManager.ConnectionStrings("MyConnection").ToString())

    Dim ad As New SqlDataAdapter
    Dim selectSQL As String = "SELECT BookTitle, Publisher,  Location, CallNumber, [Extra_Description] AS Description, [ISBN] FROM [New_Book_Table] WHERE [Export_to_list]='True' AND [@Category]='True'"
    Dim selectCMD As SqlCommand = New SqlCommand(selectSQL, conn)
    ad.SelectCommand = selectCMD
    selectCMD.Parameters.Add("@Category", SqlDbType.NVarChar, 30).Value = getCategoryString()
    Dim ds As New DataSet

    ad.Fill(ds)
    ListView1.DataSource = ds
    ListView1.DataBind()

但是得到错误：System.Data.SqlClient.SqlException: Invalid column name '@Category'.

我想因为这不是正确的方法。我怎样才能做到这一点？我可以通过查询字符串获取列名。我想将该列名称传递给查询，并将其识别为列。

Answer 1

好吧我想出来了，这比尝试动态添加参数更简单，因为最初的SelectSQL只是一个字符串，我用以下函数动态构造了该字符串：

Protected Function getSQLQuery() As String
    Dim baseQuery As String = "SELECT BookTitle, Publisher,  Location, CallNumber, [Extra_Description] AS Description, [ISBN] FROM [New_Book_Table] WHERE [Export_to_list]='True'"
    Dim category As String = getCategoryString()
    Return baseQuery & "AND [" & category & "]='True'"
End Function

使用SQLDataAdapter查询动态列名

1 个答案: