Single plus operator in javascript

This question already has an answer here:

What does = +_ mean in JavaScript 12 answers

---

The plus converts a string to a float. The code you provided is equivalent to the following:

if ( obj.length === Number(obj.length) ) {
    // ...
}

链接地址: http://www.djcxy.com/p/73928.html

上一篇: 0，'='之后的'+'做什么？

下一篇: JavaScript中的单加操作符