讓前端基礎筆試更優秀（360）

1.

window.val = 1;
var json = {
  val:10,
  dbl:function(){
     this.val*=2;
  }
}
json.dbl();
var dbl = json.dbl;
dbl();
json.dbl.call(window);
alert(window.val + json.val);

2.

(function(){
   var val = 1;
   var json = {
          val:10,
          dbl:function(){
             val*=2;  
          }   
   };
   json.dbl();
   alert(json.val+val);
}());

3.

function C1(name){
   if(name)this.name = name;
}

function C2(name){
   this.name = name;
}

function C3(name){
   this.name = name || 'json';
}

C1.prototype.name='Tom';
C2.prototype.name='Tom';
C3.prototype.name='Tom';
alert((new C1().name)+(new C2().name)+(new C3().name));

4.

var test = (function(i){
    return function(){
        alert(i*=2);
    }
})(2);
test(5);