The simple implementation of native AJAX encapsulation _ajax related

Return to the original JS, the Internet to see the AJAX package, then take to change, I do not know what the drawbacks, I hope to point out!

var ajaxhelper = {/*1.0 browser-compatible way to create asynchronous object/Makexhr:function () {//Declare asynchronous object variable var xmlHttp = false; DECLARE extension var xmlhttpobj = ["msxml2.xmlhttp.5.0", "msxml2.xmlhttp.4.0", "msxml2.xmlhttp.3.0", "Msxml2.xmlhttp", "MSXML .
    XMLHttp "]; To determine whether the browser supports XMLHttpRequest, and if so, a new browser that creates the if window directly.
    XMLHttpRequest) {xmlHttp = new XMLHttpRequest (); //Otherwise, you can only iterate through the old browser asynchronous object name and try to create it until the creation is successful. else if window.
        ActiveXObject) {for (i = 0; i < xmlhttpobj.length; i++) {xmlHttp = new ActiveXObject (xmlhttpobj[i));
        if (xmlHttp) {break; Determine if the asynchronous object was created successfully and, if successful, return the asynchronous object or false return XmlHttp?
  Xmlhttp:false;
    /*2.0 Send Ajax Request * * Doajax:function (method, URL, data, Isayn, callback, type) {method = Method.tolowercase ();
    2.1 Create asynchronous object var xhr = THIS.MAKEXHR (); 2.2 Set the request parameter (if it is get, then with the URL parameter, if not, without) Xhr.open (method, url + (method = = "Got"?)
    "?" + Data: ""), Isayn); 2.3 According to pleasepredicate (get/post), add a different request header if (method = = "Get") {Xhr.setrequestheader ("if-modified-since", 0);
    else {xhr.setrequestheader ("Content-type", "application/x-www-form-urlencoded");
        //2.4 Set callback function Xhr.onreadystatechange = function () {//If the response message sent back by the server is received if (Xhr.readystate = 4) { Determine if the status code is normal if (xhr.status = =) {if (type.tolowercase () = "json") {var ret = {}
            ;
              try {if (typeof JSON!= "undefined") {ret = Json.parse (xhr.responsetext);
              } else {//IE8 does not support JSON ret = new Function ("return" + Xhr.responsetext) ();
            Callback (ret);
              catch (E) {console.log (e.message);
            Callback (FALSE);
          } else {//Direct return text callback (Xhr.responsetext); } else {Console.log ("AJAX Status Code:" + Xhr.staTUS);
        Callback (FALSE);
    }
      }
    };
  2.5 Send (if it is post, then pass the parameter, otherwise do not pass) Xhr.send (method!= "get"? data:null); /*3.0 send a POST request directly/dopost:function (URL, data, Isayn, callback, type) {This.doajax ("post", url, data, Isayn,
  callback, type); /*4.0 directly send GET request * * doget:function (URL, data, Isayn, callback, type) {This.doajax ("get", url, data, Isayn, Cal
  Lback, type); }
};

Assuming a requirement, the backend requires passing in two digits N1, N2, and then returns the sum.

When one of the arguments is empty or is not a number, returns: {"status": "0", "msg": "Wrong argument!" "}

When correct, return: {"status": "1", "sum": "//n1 plus n2"}

The back-end code is not posted.

Front-End calls:

document.getElementById ("Btnsubmit"). onclick = function () {
      ajaxhelper.dopost ("Backend url", "n1=10&n2=25", True, function (ret) {
        if (!ret) {return;}
        if (ret.status!= 1) {
          alert (ret.msg);
          return;
        }
        var n = ret.sum;
        var s = ret.status;
      }, "json");

The above native Ajax encapsulation of the simple implementation is a small series to share all the content, hope to give you a reference, but also hope that we support the cloud habitat community.