記錄fotas.net.call的兩個實現

1. fotas.net.call = function (uri, predefine, callback, param, timeout, retry)
2. {
3.     var uniqid = fotas.uniqid();
4.     fotas.callbacks[uniqid] = function (a) {
5.         delete fotas.callbacks[uniqid];
6.         document.body.removeChild(fotas.scripts[uniqid]);
7.         delete fotas.scripts[uniqid];
8.         Ajax = new Object();
9.         Ajax.readyState = 4;
10.         Ajax.status = 200;
11.         Ajax.responseText = a;
12.         if (callback != undefined)
13.             callback(Ajax);
14.     };
15.     if (uri.indexOf('?') != -1)
16.         uri += "&jsonp="+encodeURIComponent("fotas.callbacks["+uniqid+"]")+"&key="+fotas.key;
17.     else
18.         uri += "?jsonp="+encodeURIComponent("fotas.callbacks["+uniqid+"]")+"&key="+fotas.key;
19.     if (param != undefined)
20.         uri += "&"+param;
21.     fotas.scripts[uniqid] = document.createElement('script');
22.     fotas.scripts[uniqid].setAttribute("type","text/javascript");
23.     fotas.scripts[uniqid].src = fotas.uri+uri;
24.     document.body.appendChild(fotas.scripts[uniqid]);
25. }

1. fotas.net.call = function (uri, predefine, callback, param, timeout, retry)
2. {
3.     var Ajax = CreateXMLHttpRequest();
4.     Ajax.onreadystatechange = function () { callback(Ajax); };
5.     if (param != undefined)
6.     {
7.         Ajax.open("POST", uri, true);
8.         Ajax.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
9.         Ajax.setRequestHeader("Connection", "close");
10.         if (predefine != undefined)
11.             Ajax = predefine(Ajax);
12.         Ajax.send(param);
13.     } else {
14.         Ajax.open("GET", uri, true);
15.         if (predefine != undefined)
16.             Ajax = predefine(Ajax);
17.         if (window.XMLHttpRequest)
18.             Ajax.send(null);
19.         else if (window.ActiveXObject)
20.             Ajax.send();
21.     }
23.     if (timeout != undefined)
24.     {
25.         var trynow = 0;
26.         if (retry == undefined)
27.             retry = 0;
29.         function ConnectionCheck()
30.         {  
31.             if(Ajax.readyState != 4)
32.             {
33.                 Ajax.close();
34.                 trynow++;
35.                 if (trynow <= retry)
36.                 {
37.                     if (param != undefined)
38.                     {
39.                         Ajax.open("POST", uri, true);
40.                         Ajax.send(param);
41.                     } else {
42.                         Ajax.open("GET", uri, true);
43.                         if (window.XMLHttpRequest)
44.                             Ajax.send(null);
45.                         else if (window.ActiveXObject)
46.                             Ajax.send();
47.                     }
48.                     setTimeout(ConnectionCheck, timeout);
49.                 }
50.             }
51.         }
52.         
53.         setTimeout(ConnectionCheck, timeout);
54.     }
55. }

這兩個fotas.net.call互相相容。第一個用於跨域AJAX（JSONP），第二個是標準的XMLHttpRequest。因此第二個支援設定Timeout和Request Header。