vbnet 3DES 算法代码

下面是一个使用VB.NET实现3DES算法的示例代码：

Imports System.Security.Cryptography
Imports System.Text

Public Class Form1
    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        Dim originalText As String = "Hello World!"
        Dim key As String = "0123456789abcdef0123456789abcdef"
        Dim encryptedText As String = Encrypt(originalText, key)
        Dim decryptedText As String = Decrypt(encryptedText, key)

        MessageBox.Show("Original Text: " & originalText & vbCrLf &
                        "Encrypted Text: " & encryptedText & vbCrLf &
                        "Decrypted Text: " & decryptedText)
    End Sub

    Public Function Encrypt(plainText As String, key As String) As String
        Dim des As New TripleDESCryptoServiceProvider()
        des.Key = Encoding.UTF8.GetBytes(key)
        des.Mode = CipherMode.ECB
        des.Padding = PaddingMode.PKCS7

        Dim encryptor As ICryptoTransform = des.CreateEncryptor()
        Dim plainBytes As Byte() = Encoding.UTF8.GetBytes(plainText)
        Dim cipherBytes As Byte() = encryptor.TransformFinalBlock(plainBytes, 0, plainBytes.Length)
        encryptor.Dispose()

        Return Convert.ToBase64String(cipherBytes)
    End Function

    Public Function Decrypt(cipherText As String, key As String) As String
        Dim des As New TripleDESCryptoServiceProvider()
        des.Key = Encoding.UTF8.GetBytes(key)
        des.Mode = CipherMode.ECB
        des.Padding = PaddingMode.PKCS7

        Dim decryptor As ICryptoTransform = des.CreateDecryptor()
        Dim cipherBytes As Byte() = Convert.FromBase64String(cipherText)
        Dim plainBytes As Byte() = decryptor.TransformFinalBlock(cipherBytes, 0, cipherBytes.Length)
        decryptor.Dispose()

        Return Encoding.UTF8.GetString(plainBytes)
    End Function
End Class

在上面的代码中，我们使用TripleDESCryptoServiceProvider类来实现3DES算法。使用Encrypt函数可以将原始文本加密为Base64编码的密文，使用Decrypt函数可以将密文解密为原始文本