不使用临时变量互换两个变量的值
1.数组直取值法
var a=1,b=2;
b = [a,a=b][0];
console.log(a); //2
console.log(b); //1
2.异或法
a=a^b;
b=b^a;
a=a^b;
3..加减法
var a=1,b=2;
a = a+b;
b = a-b;
a = a-b;
console.log(a); //2
console.log(b); //1
4.类型转数组
var a=1,b=2;
a = [a,b];
b = a[0];
a = a[1];
console.log(a);//2
console.log(b);//1
5.类型转对象，赋属性
var a=1,b=2;
a = {
a:b,
b:a,
};
b =a.b;
a =a.a; //注意位置，b = a.b 要用到a 而 a = a.a 不会用到b， 所以要先取b的值
console.log(a);//2
console.log(b);//1
6.一行代码 运算赋值
var a=1,b=2;
a = b +0*(b=a);
console.log(a);
console.log(b);
7.拼接数组分隔取值
var a=1,b=2;
a = a + "," +b;
b = a;
a = a.split(",")[1];
b = b.split(",")[0];
console.log(a);
console.log(b);
8.如果为Sting类型的两个变量 可以用拼接 也可以运算
var a="hp",b="js";
a = b +((b=a)?"":"");
console.log(a);
console.log(b);