Example analysis of C#.net implementation of WeChat public account interface development

using System;
using System.Web;
using System.IO;
using System.Text;
using System.Web.Security;
using weixin_api;
public class wxgz_api : IHttpHandler
{
  public void ProcessRequest(HttpContext context)
  {
    context.Response.ContentType = "text/plain";
    string postString = string.Empty;
    if (HttpContext.Current.Request.HttpMethod.ToUpper() == "POST")
    {
      //微信服务器对接口消息
      using (Stream stream = HttpContext.Current.Request.InputStream)
      {
        Byte[] postBytes = new Byte[stream.Length];
        stream.Read(postBytes, 0, (Int32)stream.Length);
        postString = Encoding.UTF8.GetString(postBytes);
        Handle(postString);
      }
    }
    else
    {
      //微信进行的Get测试(开发者认证)
      WxAuth();
    }
  }
  /// <summary>
  /// 处理信息并应答
  /// </summary>
  private void Handle(string postStr)
  {
    messageHelp help = new messageHelp();
    string responseContent = help.ReturnMessage(postStr);
    HttpContext.Current.Response.ContentEncoding = Encoding.UTF8;
    HttpContext.Current.Response.Write(responseContent);
  }
  #region 微信验证
  public void WxAuth()
  {
    string token = "xxxxxxxx";
    if (string.IsNullOrEmpty(token))
    {
      return;
    }
    string echoString = HttpContext.Current.Request.QueryString["echostr"];
    string signature = HttpContext.Current.Request.QueryString["signature"];
    string timestamp = HttpContext.Current.Request.QueryString["timestamp"];
    string nonce = HttpContext.Current.Request.QueryString["nonce"];
    if (CheckSignature(token, signature, timestamp, nonce))
    {
      if (!string.IsNullOrEmpty(echoString))
      {
        HttpContext.Current.Response.Write(echoString);
        HttpContext.Current.Response.End();
      }
    }
  }
  /// <summary>
  /// 验证微信签名
  /// </summary>
  public bool CheckSignature(string token, string signature, string timestamp, string nonce)
  {
    string[] ArrTmp = { token, timestamp, nonce };
    Array.Sort(ArrTmp);
    string tmpStr = string.Join("", ArrTmp);
    tmpStr = FormsAuthentication.HashPasswordForStoringInConfigFile(tmpStr, "SHA1");
    tmpStr = tmpStr.ToLower();
    if (tmpStr == signature)
    {
      return true;
    }
    else
    {
      return false;
    }
  }
  #endregion
  public bool IsReusable
  {
    get
    {
      return false;
    }
  }
}