SoapHeader 變數圖解：

程式碼

SoapHeader

public class UserHeader : System.Web.Services.Protocols.SoapHeader
{
  public UserHeader() {}

  public string Username { get { return m_Username; } set { m_Username = value; } }
  private string m_Username;

  public string Password { get { return m_Password; } set { m_Password = value; } }
  private string m_Password;
}

WebService

// using System.Web.Services.Protocols;

public UserHeader m_userHeader = null;
public UserHeader UserHeader
{
  get { return m_userHeader; }
  set { m_userHeader = value; }
}

[SoapHeader("UserHeader", Direction = SoapHeaderDirection.InOut)]
[WebMethod]
public string ReturnLoginUser()
{
  string msg = "err";
  if (m_userHeader != null)
  {
    string name = Decrypt(m_userHeader.Username, m_Key, m_IV);
    string pwd = Decrypt(m_userHeader.Password, m_Key, m_IV);

    msg = name + "|" + pwd;
  } // if

  return msg;
}

Client

static void Main(string[] args)
{
  Service ws = new Service();

  string key="", iv="";
  ws.GetKeyAndIv(ref key, ref iv);

  UserHeader uh = new UserHeader();
  uh.Username = Encrypt("中文(abc)", key, iv);
  uh.Password = Encrypt("1234-ABC", key, iv);

  ws.UserHeaderValue = uh;
  Console.WriteLine("Return:{0}", ws.ReturnLoginUser());
  Console.ReadKey();
}

加密

/// <summary>
/// DEC 加密法
/// </summary>
/// <param name="txt">加密文本</param>
/// <param name="sKey">加密金鑰</param>
/// <param name="sIV">初始化向量</param>
/// <returns></returns>
public static string Encrypt(string txt, string key, string iv)
{
  System.Text.StringBuilder ret = new System.Text.StringBuilder();
  using (System.Security.Cryptography.DESCryptoServiceProvider des = new System.Security.Cryptography.DESCryptoServiceProvider())
  {
    byte[] data = System.Text.Encoding.Default.GetBytes(txt);
    des.Key = System.Text.ASCIIEncoding.ASCII.GetBytes(key);
    des.IV = System.Text.ASCIIEncoding.ASCII.GetBytes(iv);

    using (System.IO.MemoryStream ms = new System.IO.MemoryStream())
    {
      using (System.Security.Cryptography.CryptoStream cs = new System.Security.Cryptography.CryptoStream(ms, des.CreateEncryptor(), System.Security.Cryptography.CryptoStreamMode.Write))
      {
         cs.Write(data, 0, data.Length);
         cs.FlushFinalBlock();
      } // using

      foreach (byte b in ms.ToArray())
     {
        ret.AppendFormat("{0:X2}", b);
     } // foreach
    } // using
  } // using

  return ret.ToString();
}

解密

/// <summary>
/// DEC 解密法
/// </summary>
/// <param name="txt">解密的字串</param>
/// <param name="sKey">加密金鑰</param>
/// <param name="sIV">初始化向量</param>
/// <returns></returns>
public static string Decrypt(string txt, string key, string iv)
{
  using (System.Security.Cryptography.DESCryptoServiceProvider des = new System.Security.Cryptography.DESCryptoServiceProvider())
  {
    byte[] data = new byte[txt.Length / 2];
    for (int x = 0; x < txt.Length / 2; x++)
    {
      int i = (Convert.ToInt32(txt.Substring(x * 2, 2), 16));
      data[x] = (byte)i;
    } // for

    des.Key = System.Text.ASCIIEncoding.ASCII.GetBytes(key);
    des.IV = System.Text.ASCIIEncoding.ASCII.GetBytes(iv);

    using (System.IO.MemoryStream ms =
      new System.IO.MemoryStream())
    {
      using (System.Security.Cryptography.CryptoStream cs =new System.Security.Cryptography.CryptoStream(ms, des.CreateDecryptor(),System.Security.Cryptography.CryptoStreamMode.Write))
      {
        try
        {
          cs.Write(data, 0, data.Length);
          cs.FlushFinalBlock();
          return System.Text.Encoding.Default.GetString(ms.ToArray());
        } // try
        catch
        {
          return "";
        } // catch
      } // using
    } // using
  } // using
}

檔案下載：

• 程式碼（Box.net）

參考資料：

• [MSDN] SoapHeader 類別 (System.Web.Services.Protocols)
• [MSDN] DESCryptoServiceProvider 類別 (System.Security.Cryptography)
• [ASP.NET]為WebService多加上認證(SoapHeader) – Dotjum的分享空間- 點部落
• C# 加密(Encrypt) 解密(Decrypt) 使用DESCryptoServiceProvider – Phoenix.net 迷之殿- 點部落
• webservice 用戶驗證 加密 – Hetter – 博客園
• asp.net 2.0中傻瓜式使用soap header – jackyrong – 博客園

分析：

• 前 4 次連線是第一次載入時的頁面（default.aspx）本身及 3 個 AJAX 相關的 script 檔。Response：9,097。
  第 5 次是按「選項1」。Response：1,042。
  第 6 次是按「__doPostBack.1」。Response：1,042。
  第 7 次是按「__doPostBack.2」。Response：1,042。
• 但 Request 的長度則略有不同。

用 UpdatePanel 的方式確實比原本整頁 postback 好。

但要注意：Page_Load 在普通的 postback  和 partial postback 都會執行（圖）。可以藉由 IsPostBack 和 IsInAsyncPostBack 來判斷兩者的差異。

可用 __doPostBack 第二個參數傳遞參數。

Server Side 流程

//==========================
// 第一次載入
Page_Load
    IsPostBack=False
    IsInAsyncPostBack=False
    __EVENTTARGET=, __EVENTARGUMENT=
UpdatePanel1_PreRender
//==========================
// 按「選項1」
Page_Load
    IsPostBack=True
    IsInAsyncPostBack=True
    __EVENTTARGET=, __EVENTARGUMENT=
Button1_Click
UpdatePanel1_PreRender
==========================
// 按「__doPostBack.1」
Page_Load
    IsPostBack=True
    IsInAsyncPostBack=True
    __EVENTTARGET=UpdatePanel1, __EVENTARGUMENT=參數1,參數2
UpdatePanel1_PreRender
==========================
// 按「__doPostBack.2」
Page_Load
    IsPostBack=True
    IsInAsyncPostBack=True
    __EVENTTARGET=UpdatePanel1, __EVENTARGUMENT=
UpdatePanel1_PreRender
==========================
// 按「清除」
Page_Load
    IsPostBack=True
    IsInAsyncPostBack=False
    __EVENTTARGET=UpdatePanel1, __EVENTARGUMENT=
UpdatePanel1_PreRender

程式碼

default.aspx

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="WebApplication1._Default" %>
<%@ Register assembly="System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" namespace="System.Web.UI" tagprefix="asp" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
  <title></title>
</head>
<body>
 <form id="form1" runat="server"><div>
    <asp:ScriptManager ID="ScriptManager1" runat="server">
    </asp:ScriptManager>

    <asp:UpdatePanel ID="UpdatePanel1" runat="server"
    onprerender="UpdatePanel1_PreRender">
    <ContentTemplate>

    票數：<asp:Label ID="Label1" runat="server" Text="Label"></asp:Label><br />
    <asp:Button ID="Button1" runat="server" Text="選項1" onclick="Button1_Click" />
    <asp:Button ID="Button2" runat="server" Text="選項2" onclick="Button2_Click" />
    <br />
    <input type="button" value="__doPostBack.1" name="btn1" id="btn1" onclick="__doPostBack('UpdatePanel1', '參數1,參數2');" />
    <input type="button" value="__doPostBack.2" name="btn2" id="btn2" onclick="__doPostBack('UpdatePanel1', '');" />
    <br />裡面：<%=DateTime.Now.ToString() %>
    </ContentTemplate>

    </asp:UpdatePanel>
    <asp:Button ID="btnReset" runat="server" Text="清除" onclick="btnReset_Click" />
    <br />外面：<%=DateTime.Now.ToString() %>
</div></form></body></html>

default.aspx.cs

using System;
using System.Diagnostics;
using System.Collections.Generic;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace WebApplication1
{
 public partial class _Default : System.Web.UI.Page
 {
  protected void Page_Load(object sender, EventArgs e)
  {
   Debug.WriteLine("==========================rnPage_Load");
   Debug.WriteLine(string.Format("tIsPostBack={0}", this.IsPostBack));
   Debug.WriteLine(string.Format("tIsInAsyncPostBack={0}", this.ScriptManager1.IsInAsyncPostBack));
   Debug.WriteLine(string.Format("t__EVENTTARGET={0}, __EVENTARGUMENT={1}", Request["__EVENTTARGET"], Request["__EVENTARGUMENT"]));

   if (Session["0"] == null)
   {
    Session["0"] = 0;
    Session["1"] = 0;
   } // if

   ShowResult();
  }

  protected void Button1_Click(object sender, EventArgs e)
  {
   Debug.WriteLine("Button1_Click");
   Session["0"] = Int32.Parse(Session["0"].ToString()) + 1;
   ShowResult();
  }

  protected void Button2_Click(object sender, EventArgs e)
  {
   Debug.WriteLine("Button2_Click");
   Session["1"] = Int32.Parse(Session["1"].ToString()) + 1;
   ShowResult();
  }

  private void ShowResult()
  {
   this.Label1.Text = string.Format("1:{0}, 2:{1}", Session["0"], Session["1"]);
  }

  protected void btnReset_Click(object sender, EventArgs e)
  {
   Session["0"] = 0;
   Session["1"] = 0;
   ShowResult();
  }

  protected void UpdatePanel1_PreRender(object sender, EventArgs e)
  {
   Debug.WriteLine("UpdatePanel1_PreRender");
  }
 }
}

檔案下載

• 程式碼（Box.net）

參考資料

• Are you making these 3 common ASP.NET AJAX mistakes? | Encosia
• Easily refresh an UpdatePanel, using JavaScript | Encosia
• UpdatePanel and __doPostBack – ASP.NET Forums
• [MSDN] Generating Client-Side Script for Postback
• [MSDN] ASP.NET Page Life Cycle Overview