text: /**
   * Created by jal on 2018/3/21 0021.
   */
  var net = new Object();
  net.AjaxRequest = function (url,onload,onerror,method,params) {
      this.req = null;
      this.onload = onload;
      this.onerror = (onerror)?onerror:this.defaultError;
      this.loadDate(url,method,params);
  }
  net.AjaxRequest.prototype.loadDate = function (url,method,params) {
      if(!method){
          method = "GET";
      }
      if (window.XMLHttpRequest){
          this.req = new XMLHttpRequest();
      }else if (window.ActiveXObject){
          this.req = new ActiveXObject("Microsoft.XMLHTTP");
      }
      if (this.req){
          try{
              var loader = this;
              this.req.onreadystatechange = function () {
                  net.AjaxRequest.onReadyState.call(loader);
              }
              this.req.open(method,url,true);
              this.req.send();
          }catch (err){
              this.onerror.call(this);
          }
      }
  }
  net.AjaxRequest.onReadyState = function () {
      var req = this.req;
      var ready = req.readyState;
      if (ready == 4){
          if(req.status == 200){
              this.onload.call(this);
          }else {
              this.onerror.call(this);
          }
      }
  }
  net.AjaxRequest.prototype.defaultError = function () {
      alert("error fetching data!\n\nreadyState:"+this.req.readyState+"\nstatus: "+this.req.status+"\nheaders: "+this.req.getAllResponseHeaders() );
  }