js输出结果题汇总

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	var a = 1;
function Fn1(){
var a = 2;
console.log(this.a + a);
}
function Fn2(){
var a = 10;
Fn1();
}
Fn2();
var Fn3 = function(){
this.a = 3;
}
Fn3.prototype = {
a:4
}
var fn3 = new Fn3();
Fn1.call(fn3);

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	var obj = {"key":"1","value":"2"};
var newObj = obj;
newObj.value += obj.key;
console.log(obj.value);

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	var m = 1, j=k=0;
function add(n){
return n = n+1;
}
y = add(m);
function add(n){
return n = n + 3;
}
z=add(m);
console.log(y + ',' + z);

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	function create(){
let b = 100;
return function(){
console.log(b);
}
}
let fn = create();
let b = 200;
fn();

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	function print(fn1){
let d = 200;
fn1();
}
let d = 100;
function fn1(){
console.log(d);
}
print(fn1);

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function fn1(){
console.log(this);
}
fn1();

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function fn1(){
console.log(this);
}
fn1.call({x: 100});

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function fn1(){
console.log(this);
}
const fn2 = fn1.bind({x:100});
fn2();

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const zhangsan = {
name: '张三',
sayHi(){
// this即当前对象
console.log(this);
},
wait(){
setTimeout(function(){
// this === window
console.log(this);
})
}
}

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class People{
constructor(name){
this.name = name;
this.age = 20;
}
sayHi(){
console.log(this);
}
}
const zhangsan = new People('张三');
zhangsan.sayHi();

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const zhangsan = {
name: '张三',
sayHi(){
// this即当前对象
console.log(this);
},
wait(){
setTimeout(() => {
// this即当前对象
console.log(this);
})
}
}

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let i
for(i = 0; i <=3; i++){
setTimeout(function(){
console.log(i)
}, 0)
}

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for(let i = 0; i <=3; i++){
setTimeout(function(){
console.log(i)
}, 0)
}

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let a = 100
function test(){
alert(a)
a = 10
alert(a)
}
test()
alert(a)