Question

我们正在使用 ASCIIEncoding 来保存数据，我们对支持Unicode值（区域语言（如（印地语，古吉拉特语）等）有新的要求，因此我们对代码进行了如下修改，我们并没有做大的改动只需将 ASCIIEncoding 更改为 UnicodeEncoding 。问题是我们无法使用 UnicodeEncoding

解密旧记录

有什么方法可以从存储在数据库中的加密字符串中识别加密方法

我们正在使用以下代码

Public Function DESEncrypt(ByVal PlainText As String) As String
    Dim KeyBArray As Byte()
    Dim IVBArray As Byte()
    Dim Encryptor As ICryptoTransform
    Dim PlainTextBArray As Byte()
    'Dim Ascii As New ASCIIEncoding 
    Dim Ascii As New UnicodeEncoding 
    Dim I As Integer
    Dim Result As String

    PlainTextBArray = Ascii.GetBytes(PlainText)
    KeyBArray = Convert.FromBase64String(desKey)
    IVBArray = Convert.FromBase64String(desIV)

    Dim TDES As New TripleDESCryptoServiceProvider
    Encryptor = TDES.CreateEncryptor(KeyBArray, IVBArray)      

    Dim CypherTextBArray(Encryptor.OutputBlockSize - 1) As Byte
    CypherTextBArray = Encryptor.TransformFinalBlock(PlainTextBArray, I, PlainTextBArray.Length)
    Dim TempBArray(CypherTextBArray.Length - 1) As Byte
    For I = 0 To CypherTextBArray.Length - 1
        TempBArray(I) = CypherTextBArray(I)
    Next
    Result = Convert.ToBase64String(TempBArray)
    KeyBArray = Nothing
    IVBArray = Nothing
    Encryptor = Nothing
    PlainTextBArray = Nothing
    Ascii = Nothing
    Return Result
End Function

Public Function DESDecrypt(ByVal CypherText As String) As String
    Dim KeyBArray As Byte()
    Dim IVBArray As Byte()       
    Dim CypherTextBArray As Byte()
    Dim Decryptor As ICryptoTransform
    Dim PlainText As New StringBuilder("")
    Dim I As Integer
    Dim Result As String = String.Empty

    If CypherText <> "" Then
        CypherTextBArray = Convert.FromBase64String(CypherText)
        KeyBArray = Convert.FromBase64String(desKey)
        IVBArray = Convert.FromBase64String(desIV)

        If cryptoPrivider = "TripleDES" Or cryptoPrivider = "CITripleDES" Then
            Dim TDES As New TripleDESCryptoServiceProvider
            Decryptor = TDES.CreateDecryptor(KeyBArray, IVBArray)
        Else
            Dim DES As New DESCryptoServiceProvider
            Decryptor = DES.CreateDecryptor(KeyBArray, IVBArray)
        End If

        Dim PlainTextBArray(Decryptor.OutputBlockSize - 1) As Byte

        PlainTextBArray = Decryptor.TransformFinalBlock(CypherTextBArray, I, CypherTextBArray.Length)
        'Result = System.Text.Encoding.ASCII.GetString(PlainTextBArray) 
        Result = System.Text.Encoding.Unicode.GetString(PlainTextBArray) 

    End If        
    KeyBArray = Nothing
    IVBArray = Nothing
    CypherTextBArray = Nothing
    Decryptor = Nothing
    PlainText = Nothing
    Return Result
End Function

Answer 1

您应该使用 UTF8Encoding 而不是 UnicodeEncoding 。后者使用UTF16编码，因此不兼容ASCII的字节。相反，UTF8与ASCII字节兼容。两者都支持所有Unicode代码，因此不会丢失任何信息。

但是通常没有一个超级集编码器很不幸。因此，通常您应该跟踪编码（例如，在新字段中），或者只使用一种编码（以便转换所有数据库）。

我们如何通过加密字符串识别ASCII或Unicode编码？

1 个答案: