js delete删除对象属性,delete删除不了变量及原型链中的变量 一.delete删除对象属性 function fun(){ this.name = 'gg'; } var obj = new fun(); console.log(obj.name);//gg delete obj.name; console.log(obj.name); //undefined 二.delete删除不了变量 var name = 'gg'; delete name; console.log(name)…

node.js delete directory & file system delete a not empty directory https://nodejs.org/api/fs.htm fs.rmdir(path[, options], callback) fs.rmdirSync(path[, options]) recursive: true In a Node.js application, you can use the fs.rmdir() method to delete…

1,对象属性删除   function fun(){ this.name = 'mm'; } var obj = new fun(); console.log(obj.name);//mm delete obj.name; console.log(obj.name); //undefined   2,变量删除   var name = 'lily'; delete name; console.log(name); //lily   直接用delelte删除不了变量   3,删除不了原型链中的变量…

1,对象属性删除 function fun(){ this.name = 'mm'; } var obj = new fun(); console.log(obj.name);//mm delete obj.name; console.log(obj.name); //undefined 2,变量删除 var name = 'lily'; delete name; console.log(name); //lily 直接用delelte删除不了变量 3,删除不了原型链中的变量 fun.proto…

,对象属性删除 function fun(){ this.name = 'mm'; } var obj = new fun(); console.log(obj.name);//mm delete obj.name; console.log(obj.name); //undefined ,变量删除 var name = 'lily'; delete name; console.log(name); //lily 直接用delelte删除不了变量 ,删除不了原型链中的变量 fun.prototyp…

delete操作符很陌生,很少会用到,但是既然碰到了,就mark一下: delete 操作符用于删除一个对象的属性: 注意点:只能删除自己的属性,从原型链上继承的属性是无法删除的:…

在开始之前,先让我们看一段代码 >>> var sum = function(a, b) {return a + b;} >>> var add = sum; >>> delete sum true >>> typeof sum; "undefined" 这段代码是Firebug控制台里的实际结果,初看这段代码,你觉得有什么问题?但我要说的是,删除sum应该是失败的,同时typeof sum的结果不应该是undef…

1.对象属性删除 <script> function fun(){ this.name = 'mm'; } var obj = new fun(); console.log(obj.name);//mm delete obj.name; console.log(obj.name); //undefined </script> 2.变量删除 <script> var name = 'lily'; delete name; console.log(name); //name…

You can find/fork the sample project on GitHub Hey! This and all my other tutorials will soon be moving to a new home at CloseBrace, a site for JavaScript developers. You should totally click that link right now, and sign up to be alerted when the si…

想了解delete的机制缘起一个现象,我无法解释,也无法理解. 首先看一下下面这个例子: var x = 1; delete x; //false 然后我又执行了一次: y = 2; delete y; //true 看到上面的结果,我比较吃惊,为什么同样是删除,区别怎么这么大呢?进而我想学习和了解一下JS delete的机制.  在MDN(Mozilla Developer Network)上看到下面一个例子 x = 42; // creates the property x on the g…