一个调用ATL Server WebServices 的AJAX客户端

请将下面的代码完整复制到soapclient.js中

/**/
  /*****************************************************************************
 AJAX
 Javascript "SOAP Client" library
 Thank to Mr.Matteo Casati, Ihar Voitka - http://www.guru4.net/
 Author: ZhangLiang, E-Mail:[email protected]
 Date: 2006-8-31
*****************************************************************************/
  
  function
   _debug(rownum, msg) 
  ...
  {    alert(rownum+":"+msg);  }
  

  var
   SOAP_SUCCESS 
  =
   
  0
  ;
  var
   SOAP_FAULT 
  =
   
  1
  ;

  var
   _sr_env_hdr_ 
  =
    
  "
  <soap:Envelope 
  "
   
  +
  
     
  "
  xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/" 
  "
   
  +
   
     
  "
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
  "
   
  +
   
     
  "
  xmlns:xsd="http://www.w3.org/2001/XMLSchema" 
  "
   
  +
   
     
  "
  xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/">
  "
  ;
               
  var
   _sr_body_hdr_ 
  =
   
  "
  <soap:Body soap:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/">
  "
  ;

  var
   _soap_header_m_token_ 
  =
   
  ""
  ;        
  //
   global varible, soap_header: m_token
  
  
  function
   SOAPParams(callid, url, method, async, callback, username, password)
  ...
  {
    this.callid = callid;
    this.url =     url;    // "http://localhost/MtkWebgisServer/MtkWebgis.dll?Handler=GenMtkWebgisWSDL";
    this.svc = null;    //"http://cl2/MtkWebgisServer/MtkWebgis.dll?Handler=Default";    // 未完
    this.method = method;
        
    if (async+"" == "undefined")
        this.async = true;                    // default value
    else
        this.async = async;
        
    if (this.async)...{
        if (callback+"" == "undefined")
            this.callback = soap_callback;
        else
            this.callback = callback;
    }
        
    this.username = null;
    if (username+"" != "")
        this.username = username;
        
    this.password = null;
    if (password+"" != "")
        this.password = password;
        
    this.wsdl = null;
    this.result = SOAP_FAULT;
    this.xmlhttp = null;            // xmlhttp object returned
    
    this._pl = new Array();            // input parameters list
        
    this.add = function(name, value)...{
        this._pl[name] = value;
        return this;
    }
    
    this.toXml = function()...{
        var xml = "";
        for(var p in this._pl)...{
            var t = typeof(this._pl[p]);
            if (t == "object" || t == "function")
                xml += "<" + p + ">" + this._pl[p].toXml() + "</" + p + ">";
            else
                xml += "<" + p + ">" + this._pl[p].toString().replace(/&/g, "&").replace(/</g, "<").replace(/>/g, ">") + "</" + p + ">";
        }
        return xml;    
    }
    
    this.setToken = function()...{
        if (this.method=="login")...{
            _soap_header_m_token_ = this.getval("snp:m_token");
        }
    }
    
    this.getToken = function()...{
        return _soap_header_m_token_;
    }
    
    this.getval = function(name)...{
        var ret = SOAPClient._getElementsByTagName(this.xmlhttp.responseXML.documentElement, name).item(0);
        return ret.text;    
    }
    
    this.retval = function()...{
        return this.getval("return");
    }
        
    // SOAP:Fault
    this.faultcode = function()...{
        return this.getval("faultcode");
    }
    
    this.faultstring = function()...{
        return this.getval("faultstring");
    }
    
    this.faultdetail = function()...{
        return this.getval("detail");
    }
}
  

  function
   SOAPClient()
  ...
  {}
  

SOAPClient.invoke 
  =
   
  function
  (params)
  ...
  {
    params.result = SOAP_FAULT;
    if(params.async)
        SOAPClient._loadWsdl(params);
    else
        return SOAPClient._loadWsdl(params);
}
  

  //
   private: wsdl cache
  
  SOAPClient_cacheWsdl 
  =
   
  new
   Array();

  //
   private: invoke async
  
  SOAPClient._loadWsdl 
  =
   
  function
  (params)
  ...
  {
    // load from cache?
    params.wsdl = SOAPClient_cacheWsdl[params.url];
    if(params.wsdl + "" != "" && params.wsdl + "" != "undefined")...{
        params.svc = SOAPClient._getService(params.wsdl);    
        return SOAPClient._sendSoapRequest(params);
    }
        
    // get wsdl
    var _xmlhttp = SOAPClient._getXmlHttp();
    
    if (params.username+"" != "undefined")
        _xmlhttp.open("GET", params.url, params.async, params.username, params.password);
    else
        _xmlhttp.open("GET", params.url, params.async);
    
    if(params.async)...{
        _xmlhttp.onreadystatechange = function()...{
            if(_xmlhttp.readyState == 4)
                SOAPClient._onLoadWsdl(params, _xmlhttp);
        }
    }
    
    _xmlhttp.send(null);
    if (!params.async)
        return SOAPClient._onLoadWsdl(params, _xmlhttp);
}
  

SOAPClient._onLoadWsdl 
  =
   
  function
  (params, req)
  ...
  {
    if (req.readyState == 4 && req.status == 200)...{
        params.wsdl = req.responseXML;
        params.svc = SOAPClient._getService(params.wsdl); 
        SOAPClient_cacheWsdl[params.url] = params.wsdl;        // save a copy in cache
        return SOAPClient._sendSoapRequest(params);
    }
    return SOAP_FAULT;
}
  

SOAPClient._sendSoapRequest 
  =
   
  function
  (params)
  ...
  {
    // get namespace, ok
    var ns = SOAPClient._getAttribValue(params.wsdl.documentElement, "targetNamespace");

    // 构造SOAP请求, SOAP 2.0
    var sr =     _sr_env_hdr_ + "<soap:Header><snp:m_token xmlns:snp=""+ns+"">" + 
                _soap_header_m_token_ + "</snp:m_token></soap:Header>" +
                _sr_body_hdr_ + "<snp:" + params.method + " xmlns:snp="" + ns + "">" + 
                params.toXml() + "</snp:" + params.method + "></soap:Body></soap:Envelope>";
    
    // send request
    params.xmlhttp = SOAPClient._getXmlHttp();
    params.xmlhttp.open("POST", params.svc, params.async);
    params.xmlhttp.setRequestHeader("SOAPAction", ""#"+params.method+""");    // SOAPAction: "#HelloWorld"
    params.xmlhttp.setRequestHeader("Content-Type", "text/xml; charset=utf-8");
    
    if(params.async)...{
        params.xmlhttp.onreadystatechange = function()...{
            if(params.xmlhttp.readyState == 4)
                SOAPClient._onSendSoapRequest(params);
        }
    }
    
    try...{
        params.xmlhttp.send(sr);
    }
    catch(ex)...{}
        
    if (!params.async)
        return SOAPClient._onSendSoapRequest(params);
}
  

SOAPClient._onSendSoapRequest 
  =
   
  function
  (params)
  ...
  {
    if (params.xmlhttp.readyState == 4 && params.xmlhttp.status == 200)...{
        params.result = SOAP_SUCCESS;    // 未完...
        params.setToken();                // 设置全局变量: _soap_header_m_token_
    }
        
    if(params.async && params.callback)
        params.callback(params.result, params);
    
    if (!params.async)
        return params.result;
}
  

  //
   private: utils
  
  SOAPClient._getElementsByTagName 
  =
   
  function
  (document, tagName, ns)
  ...
  {    
    try...{    
        // trying to get node omitting any namespaces (latest versions of MSXML.XMLDocument)
        var lst = document.selectNodes(".//*[local-name()=""+ tagName +""]");
        if (lst.length == 0)
            throw 0;
        return lst;
    }
    catch (ex)...{}
        
    // old XML parser support
    if (ns+"" == "undefined")
        return document.getElementsByTagName(tagName);
    
    return document.getElementsByTagName(ns+":"+tagName);    
}
  

SOAPClient._getService 
  =
   
  function
  (wsdl)
  ...
  {
    var soap_address = SOAPClient._getElementsByTagName(wsdl.documentElement, "address", "soap").item(0);
    return SOAPClient._getAttribValue(soap_address, "location");
}
  

SOAPClient._getAttribValue 
  =
   
  function
  (node, name)
  ...
  {
    return (node.attributes[name]+"" == "undefined") ? node.attributes.getNamedItem(name).nodeValue : node.attributes[name].value;
}
  

  //
   private: xmlhttp factory
  
  SOAPClient._getXmlHttp 
  =
   
  function
  () 
  ...
  {
    try...{
        if(window.XMLHttpRequest)...{
            var req = new XMLHttpRequest();
            // some versions of Moz do not support the readyState property and the onreadystate event so we patch it!
            if(req.readyState == null) 
            ...{
                req.readyState = 1;
                req.addEventListener("load", 
                                    function() 
                                    ...{
                                        req.readyState = 4;
                                        if(typeof req.onreadystatechange == "function")
                                            req.onreadystatechange();
                                    },
                                    false);
            }
            return req;
        }
        else if(window.ActiveXObject) ...{
            return new ActiveXObject(SOAPClient._getXmlHttpProgID());
        }
    }
    catch (ex) ...{}
    
    throw new Error("Your browser does not support XmlHttp objects");
}
  

SOAPClient._getXmlHttpProgID 
  =
   
  function
  ()
  ...
  {
    if(SOAPClient._getXmlHttpProgID.progid)
        return SOAPClient._getXmlHttpProgID.progid;
    var progids = ["Msxml2.XMLHTTP.5.0", "Msxml2.XMLHTTP.4.0", "MSXML2.XMLHTTP.3.0", "MSXML2.XMLHTTP", "Microsoft.XMLHTTP"];
    var o;
    for(var i = 0; i < progids.length; i++)
    ...{
        try
        ...{
            o = new ActiveXObject(progids[i]);
            return SOAPClient._getXmlHttpProgID.progid = progids[i];
        }
        catch (ex) ...{};
    }
    throw new Error("Could not find an installed XML parser");
} 
假设ATL XML WebServices实现方法如下：
 
  
[id(  1
  ), helpstring(
  "
  登入系统, 获得用户令牌和全图URL, 以后任何方法调用必须给出令牌
  "
  )]

HRESULT login([  in
  ] BSTR Username, [
  in
  ] BSTR Password);

id(  2
  ), helpstring(
  "
  刷新地图, 取地图imgURL
  "
  )]

HRESULT refresh([out] DOUBLE  *
   Scale, [out, retval] BSTR 
  *
  imgURL);
 
客户端IE中调用如下：
 
  
<  HTML  >
  
      <  HEAD
  >
  
          <  TITLE
  >
  WebGis Demo Page 
  -
   WebGis AJAX Client
  </
  TITLE
  >
  
          <  script language
  =
  "
  javascript
  "
   src
  =
  "
  ajax/soapclient.js
  "
  ></
  script
  >
  
          <  script language
  =
  "
  javascript
  "
  >
  
              //   WebService URL
  
              
  var
   g_url 
  =
   
  "
  http://cl2/mtkwebgis/MtkWebgis.dll?Handler=GenMtkWebgisWSDL
  "
  ;
                        
              function   soap_callback(rcode, params)
              ...  {
                if (rcode == SOAP_SUCCESS)
                ...{
                    switch (params.callid)
                    ...{
                    case "刷新":
                        imgMap.src = params.retval();                    // retval()    取得[out,retval]参数
                        alert( "当前比例:" + params.getval("Scale") );    // getval(...) 取得[out]参数
                        break;                    
                    }
                }
                else
                ...{
                    alert(params.callid+":发生错误");                    
                }                
            }  
            
              function   Login()
              ...  {
                // 同步调用, 获得令牌 
                var soap = new SOAPParams("登录", g_url, "login", false);
                soap.add("Username", "cheung");
                soap.add("Password", "mine");
                if (SOAP_SUCCESS == SOAPClient.invoke(soap))
                    refresh();
                else
                    alert("登录失败");                    
            }  
            
              function   Refresh()
              ...  {
                // 异步调用刷新, 默认回调函数soap_callback
                var soap = new SOAPParams("刷新", g_url, "refresh");
                SOAPClient.invoke(soap);
            }  
          </  script
  >
  
      </  HEAD
  >
  
      <  BODY onl oad
  =
  "
  Login();
  "
  >
  
          <  div id
  =
  "
  divMap
  "
  ><
  img id
  =
  "
  imgMap
  "
  ></
  div
  >
  
      </  BODY
  >
  
  </
  HTML
  >

使用soapclient.js需要注意，我假设XML WebServices必须存在如上面所示的login方法，用于验证用户，而且m_token必须是soap头。login原型如下：

[ soap_method ]
[ soap_header( value   =     "
  m_token
  "
  , out 
  =
   
  true
   ) ]
HRESULT login(  /**/  /*[in]*/   BSTR Username, 
  /**/
  /*[in]*/
   BSTR Password)
  ...
  {        
    CHAR szID[MAX_TOKEN_LEN + 1];
    *szID = 0;

    DWORD dwSize = MAX_TOKEN_LEN;
    HRESULT hr =  m_spSessionSvc->CreateNewSession(szID, &dwSize, &m_spSession);
    CHECK_FAILED(hr);

    szID[dwSize] = 0;
    m_token = CComBSTR(szID).Detach();
            
    return hr;
}

这样，用户就可以通过soapclient.js在IE中直接调用ATL Server写的XML WebServices了。

(本文写于2006年9月，cheungmine，上海新区时空信息技术有限公司)