前端工程师面试题JavaScript部分（第五季）

alert(‘1‘+1)//11，不是2，这个容易忘

(function(){
     var a = b = 6; 
})()

console.log(b);//6全局变量声明

function test(){
  console.log(a);
  console.log(foo());
  var a = 1;
  function foo(){
     return 2;
  }
}
 test();

var fullname = ‘John Doe‘;
var obj = {
  fullname : ‘Colin Ihrig‘,
  prop : {
     fullname: ‘Aurelio De Rosa‘,
     getFullname : function(){
        return this.fullname;
     }
  }
}
console.log(obj.prop.getFullname());
var test = obj.prop.getFullname;
console.log(test())‘

function delegateEvent (interfaceEle, selector, type, fn){
    if(interfaceEle.addEventListener){
         interfaceEle.addEventListener(type,eventfn,false);
    }  
    else{
        interfaceEle.attach(‘on‘+type,evetnfn);
    }
    function eventfn(e){
     var e = e|| window.event;
     var target = e.target || e.srcElement;
     if(matchSelecter(target,selector)){//a 是否是a
          if(fn){
                 fn.call(target,e);
          }
     }
   }
}

function mathcSelector(ele,selector){
   if(selector.charAt(0)===‘#‘){
      return ele.id == selector.slice(1);
   }
   if(selector.charAt(0)==‘.‘){
      return (" " + ele.className+‘  ‘.indexOf(‘ ‘ + selector.slice(1)+‘ ‘) != -1)
    return ele.targetName.toLowerCase()===slector.toLowerCase();
   }
}
var odiv = docyment.getElementById("oDiv");
delegateEvent(oDiv,‘a‘,‘click‘,function(){
  alert(1)
})