在ASP.NET中提供了加密的功能。名字空間System.Web.Security中包含了類FormsAuthentication，其中有一個(gè)方法HashPasswordForStoringInConfigFile。這個(gè)方法可以將用戶提供的字符變成亂碼，然后存儲(chǔ)起來。注意此方法是不能繼承的。
下面的代碼就是在做注冊頁面時(shí)將數(shù)據(jù)加密后存儲(chǔ)到數(shù)據(jù)庫的過程
Imports System.Web.Security
Imports System.Data
Imports System.Data.SqlClient '////////所需要的名稱空間

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim PassFormate As String
'///////////////EncryptPassword調(diào)用函數(shù)
PassFormate = EncryptPassword(uid.Text, "md5") '//////////或者是EncryptPassword(uid.Text, "sha1")
'TextBox2.Text = EncryptPassword(uid.Text, "md5")
'TextBox3.Text = EncryptPassword(uid.Text, "sha1")
'///////////這些大家自己試驗(yàn)吧
'TextBox4.Text = FormsAuthentication.FormsCookieName
'TextBox5.Text = FormsAuthentication.FormsCookiePath
'TextBox6.Text = FormsAuthentication.GetRedirectUrl(uid.Text, True)
'FormsAuthentication.SetAuthCookie(uid.Text, True)

Dim sql As String = "insert into pwd(uid,pwd) values(@uid,@pwd)"
Dim comm As SqlCommand = New SqlCommand(sql, conn)
conn.Open()
comm.Parameters.Add(New SqlParameter("@uid", SqlDbType.Char, 16))
comm.Parameters("@uid").Value = uid.Text
comm.Parameters.Add(New SqlParameter("@pwd", SqlDbType.Char, 16))
comm.Parameters("@pwd").Value = PassFormate
comm.ExecuteNonQuery()

End Sub

'////////////////定義加密函數(shù)，可以隨時(shí)調(diào)用。
Function EncryptPassword(ByVal password As String, ByVal passwordformate As String)
If passwordformate = "sha1" Then
EncryptPassword = FormsAuthentication.HashPasswordForStoringInConfigFile(password, "sha1")
ElseIf passwordformate = "md5" Then
EncryptPassword = FormsAuthentication.HashPasswordForStoringInConfigFile(password, "md5")
Else
EncryptPassword = ""
End If

End Function
至于用戶的驗(yàn)證也是一樣的思路了。