// 特殊类型 null
a = null;
a = Number(a);
console.log("null a转换后类型 = " + typeof a);
console.log("null a转换后的值 = " + a);
// 特殊类型 undefined
a = undefined;
a = Number(a);
console.log("undefined a转换后类型 = " + typeof a);
console.log("undefined a转换后的值 = " + a);
标签:调用,console,undefined,Number,log,类型,null,函数 From: https://www.cnblogs.com/qinglaoshi/p/17552815.html