http://jishuziyuan.com/archive/shaenxing2/6341238.html

<script>

if(1 == true){

console.log('1.ture');

}else{

console.log('1.false');

}

if(1===true){

console.log('2.true');

}else{

console.log('2.false');

}

</script>

 

log结果：

1.ture

2.false

 

实例

http://hi.baidu.com/songzongquan/item/67eaa5d8cd48bbf692a9747d

 

console.log(1&&2); //2

console.log(0&&2); //0

console.log(false&&2); //false

console.log(null&&2); //null

console.log('a'&&2); //2   

console.log(1||2); //1

console.log(0||2); //2

 

//下面是一种情况

var a;

console.log(a&&2); //undefined

//下面是一种情况

console.log(a&&2); //报错  因为没有var a