Question

你可以解释一下我可以用母版的组合框我在组合框中设置数据库名称，并通过子页调用代码如下尝试

        sqlConn = New SqlConnection(strConn)
        sqlConn.Open()
        Dim sqlda1 As SqlClient.SqlDataAdapter
        Dim sqlds1 As New DataSet

        sqlQry = "EXEC sp_databases"
        sqlda1 = New SqlDataAdapter(sqlQry, sqlConn)
        sqlda1.Fill(sqlds1, "DataBaseList")
        sqlConn.Close()
        Session.Add("dscb", " ")
        Session.Add("dscb", sqlds1.Tables("DataBaseList"))

        Dim IntPCount As Integer

        IntPCount = sqlds1.Tables("DataBaseList").Rows.Count
        'IntPCount = Session("dscb")
        Dim PCol As String
        ' cbDataBaseList.Items.Clear()
        cbDataBaseList.Items.Clear()
        cbDataBaseList.Text = "Select"

        For p = 0 To IntPCount - 1
            PCol = sqlds1.Tables("DataBaseList").Rows(p).Item("DATABASE_NAME").ToString
            If PCol.Length > 5 Then
                If PCol <> "master" Or PCol <> "msdb" Or PCol <> "tempdb" Then
                    Dim strDataBaseName As String = PCol
                    strDataBaseName = strDataBaseName.Remove(4)
                    '*** Add only "Customer's" which got the prefix "CLT_ " ***
                    If strDataBaseName = "CLT_" Then
                        NewPCol = PCol.Replace("CLT_", "")
                        NewPCol.Trim()
                        'cbDataBaseList.Items.Add(NewPCol)
                        cbDataBaseList.Items.Add(NewPCol)
                    End If
                End If
            End If
        Next
                Session.Add("CMBID", "")

        'cbDataBaseList.Text = NewPCol.ToString

        sqlds1.Dispose()
    Catch ex As Exception
        strex = ex.Message
        'MessageBox.Show(strex, "General form exception message 5.", MessageBoxButtons.OK, MessageBoxIcon.Error)
            End Try
        End If

选择索引已更改事件

会话（“CMBID”）= cbDataBaseList.Text

Answer 1

上面提到的代码是主页的Page_Load（）函数吗？如果是，那么你必须先检查

// Check if it has already been set.
if(Session("CMBID") != null) 
{
// Now if it is set, get the value
 String cmbid = (String) Session("CMBID");
//Get the post back value of the combo box  also
String cmbval = Request["<your control name>"];
// Make the above code of setting the combo box value as a separate function
FillComboBoxFromDB();
etif(!cmbval.Equals(cmbid))
{
   // set the session value with the new selected value
   Session("CMBID") = cmbval
 }


}

现在在会话中执行相同的检查并在子页面中回发值。我想这是在母版页中执行代码的小时差，子页面在设置之前试图访问会话变量。所以，只需检查会话并回发即可双重确认。

组合框选择索引已更改，将其放入母版页的会话中

1 个答案: