vb.net

Imports System.Security.Cryptography


 Public Shared Function funcMD5(ByVal str As String) As String
        Using md5Hash As MD5 = MD5.Create()
            Dim hash As String = GetMd5Hash(md5Hash,str)
            Return hash
        End Using

 End Function

 Public Shared Function GetMd5Hash(ByVal md5Hash As MD5,ByVal input As String) As String

        ' Convert the input string to a byte array and compute the hash.
        Dim data As Byte() = md5Hash.ComputeHash(Encoding.UTF8.GetBytes(input))

        ' Create a new Stringbuilder to collect the bytes
        ' and create a string.
        Dim sBuilder As New StringBuilder()

        ' Loop through each byte of the hashed data 
        ' and format each one as a hexadecimal string.
        Dim i As Integer
        For i = 0 To data.Length - 1
            sBuilder.Append(data(i).ToString("x2"))
        Next i

        ' Return the hexadecimal string.
        Return sBuilder.ToString()

 End Function 'GetMd5Hash

Dim bb as String= funcMD5(aa)    '对字符串aa进行md5加密