如何在将值添加到Listview之前解密该值？

Question

早上好，

我需要解密从我的MySQL数据库中提取的值（ccNumber），然后才将其分配给我的Listview。我该怎么做？

我设法弄清楚如何在插入数据库之前加密它，但我正在努力解密。如下面的代码所示，我正在尝试在迭代数据表（dbTable）之前调用解密子例程（DecryptCard）并将其值分配给我的Listview（ListViewCard）。但是，只有第一个记录成功，然后我收到一条错误消息（见下图）。

请注意，第一个记录已成功解密 - 但不是第二个。

我的代码如下：

代码查询数据库并将数据加载到LISTVIEW中

    Private Sub loadCard()

    Try
        'FOR MySQL DATABASE USE
        Dim dbQuery As String = ""
        Dim dbCmd As New MySqlCommand
        Dim dbAdapter As New MySqlDataAdapter
        Dim dbTable As New DataTable
        Dim i As Integer

        If dbConn.State = ConnectionState.Closed Then
            dbConn.ConnectionString = String.Format("Server={0};Port={1};Uid={2};Password={3};Database=accounting", FormLogin.ComboBoxServerIP.SelectedItem, My.Settings.DB_Port, My.Settings.DB_UserID, My.Settings.DB_Password)
            dbConn.Open()
        End If

        dbQuery = "SELECT *" & _
                   "FROM cc_master INNER JOIN customer ON customer.accountNumber = cc_master.customer_accountNumber " & _
                   "WHERE customer.accountNumber = '" & TextBoxAccount.Text & "'"
        With dbCmd
            .CommandText = dbQuery
            .Connection = dbConn
        End With
        With dbAdapter
            .SelectCommand = dbCmd
            .Fill(dbTable)
        End With
        ListViewCard.Items.Clear()
        For i = 0 To dbTable.Rows.Count - 1
            Call DecryptCard()
            With ListViewCard
                .Items.Add(dbTable.Rows(i)("ccID"))
                With .Items(.Items.Count - 1).SubItems
                    .Add(dbTable.Rows(i)("ccNumber"))
                    .Add(dbTable.Rows(i)("ccExpireMonth"))
                    .Add(dbTable.Rows(i)("ccExpireYear"))
                    .Add(dbTable.Rows(i)("ccCode"))
                    .Add(dbTable.Rows(i)("ccType"))
                    .Add(dbTable.Rows(i)("ccAuthorizedUseStart"))
                    .Add(dbTable.Rows(i)("ccAuthorizedUseEnd"))
                    .Add(dbTable.Rows(i)("nameCOMPANY"))
                    .Add(dbTable.Rows(i)("nameSALUTATION"))
                    .Add(dbTable.Rows(i)("nameLAST"))
                    .Add(dbTable.Rows(i)("nameFIRST"))
                End With
            End With
        Next
    Catch ex As MySqlException
        MessageBox.Show("A DATABASE ERROR HAS OCCURED" & vbCrLf & vbCrLf & ex.Message & vbCrLf & _
                    vbCrLf + "Please report this to the IT/Systems Helpdesk at Ext 131.")
    End Try
    dbConn.Close()

End Sub

应该解密价值的代码（ccNumber）：

    Public Sub DecryptCard()
    Dim DES As New System.Security.Cryptography.TripleDESCryptoServiceProvider
    Dim Hash As New System.Security.Cryptography.MD5CryptoServiceProvider
    Try
        DES.Key = Hash.ComputeHash(System.Text.ASCIIEncoding.ASCII.GetBytes(My.Settings.Key))
        DES.Mode = System.Security.Cryptography.CipherMode.ECB
        Dim DESDecrypter As System.Security.Cryptography.ICryptoTransform = DES.CreateDecryptor
        Dim Buffer As Byte() = Convert.FromBase64String(dbTable.Rows(0)("ccNumber").ToString())
        dbTable.Rows(0)("ccNumber") = System.Text.ASCIIEncoding.ASCII.GetString(DESDecrypter.TransformFinalBlock(Buffer, 0, Buffer.Length))
    Catch ex As Exception
        MessageBox.Show("The following error(s) have occurred: " & ex.Message, Me.Text, MessageBoxButtons.OK, MessageBoxIcon.Error)
    End Try
End Sub

这里是加密代码

    Public Sub encryptCard()
    Try
        Dim DES As New System.Security.Cryptography.TripleDESCryptoServiceProvider
        Dim Hash As New System.Security.Cryptography.MD5CryptoServiceProvider
        Dim encryptedCard As String
        DES.Key = Hash.ComputeHash(System.Text.ASCIIEncoding.ASCII.GetBytes(My.Settings.Key))
        DES.Mode = System.Security.Cryptography.CipherMode.ECB
        Dim DESEncrypter As System.Security.Cryptography.ICryptoTransform = DES.CreateEncryptor
        Dim Buffer As Byte() = System.Text.ASCIIEncoding.ASCII.GetBytes(TextBoxCard.Text)
        encryptedCard = Convert.ToBase64String(DESEncrypter.TransformFinalBlock(Buffer, 0, Buffer.Length))
    Catch ex As Exception
        MessageBox.Show("The following error(s) have occurred: " & ex.Message, Me.Text, MessageBoxButtons.OK, MessageBoxIcon.Error)
    End Try
End Sub