逗号操作符

var a = 10;

var b = 20;

var c = (a++,b++,100);

console.log(a);

console.log(b);

console.log(c);

值是11,21,100

大彻大悟了么？

 关于运算符优先级问题可以查看：

https://developer.mozilla.org/zh-CN/docs/JavaScript/Reference/Operators/Operator_Precedence