你的主页或者你管理的网站有各种密码需要保护,把密码直接放在数据库或者文件中存在不少安全隐患,所以密码加密后存储是最常见的做法。在ASP.NET中实现加密非常容易。.NET SDK中提供了CookieAuthentication类,其中的HashPasswordForStoringInConfigFile方法可直接使用MD5和SHA1算法。例子如下:
file: encrypting.aspx
<%@ Page language="c#" Codebehind="encrypting.cs" AutoEventWireup="false"
Inherits="encrypting.encrypting" %>
<html><head>
   <meta name="GENERATOR" Content="Microsoft Visual
Studio 7.0">
   <meta name="CODE_LANGUAGE"
Content="C#"></head>
 <body>
   <form method="post" runat="server">
<p> </p>
<p>
<asp:TextBox id=TextBox1 runat="server"></asp:TextBox>
<asp:Button id=Button1 runat="server"
Text="encrypting"></asp:Button></p>
<p>Encrypting Password(MD5):
<asp:Label id=MD5 runat="server"></asp:Label></p>
    </form>
 </body></html>
file:encrypting.cs
namespace encrypting
{
   using System;
   using System.Collections;
   using System.ComponentModel;
   using System.Data;
   using System.Drawing;
   using System.Web;
   using System.Web.SessionState;
   using System.Web.UI;
   using System.Web.UI.WebControls;
   using System.Web.UI.HtmlControls;
   using System.Web.Security;
   /// <summary>
   ///    Summary description for encrypting.
   /// </summary>
   public class encrypting : System.Web.UI.Page
   {
 protected System.Web.UI.WebControls.Label MD5;
 protected System.Web.UI.WebControls.Button
Button1;
 protected System.Web.UI.WebControls.TextBox
TextBox1;
public encrypting()
{
    Page.Init += new System.EventHandler(Page_Init);
       }
       protected void Page_Load(object
sender, EventArgs e)
       {
           if (!IsPostBack)
           {
               //
               // Evals
true first time browser hits the page
               //
           }
       }
       protected void Page_Init(object
sender, EventArgs e)
       {
           //
           // CODEGEN: This call is required by
the ASP+ Windows Form Designer.
           //
           InitializeComponent();
       }
       /// <summary>
       ///    Required method for Designer
support - do not modify
       ///    the contents of this method with
the code editor.
       /// </summary>
       private void InitializeComponent()
 {
  Button1.Click += new System.EventHandler
(this.Button1_Click);
  this.Load += new System.EventHandler
(this.Page_Load);
 }
 public void Button1_Click (object sender, System.EventArgs
e)
 {
  MD5.Text = CookieAuthentication.HashPasswordForStoringInConfigFile(TextBox1.Text,"MD5");
  //SHA1 use CookieAuthentication.HashPasswordForStoringInConfigFile(TextBox1.Text,"SHA1");
 }
   }
}
注意:类CookieAuthentication的namespace是System.Web.Security。