【学习笔记】JS

隐式转换

console.log('---------------------null');//fconsole.log(Boolean(null));//fconsole.log(String(null));//nullconsole.log(Number(null));//0console.log('---------------------undefined');//fconsole.log(Boolean(undefined));//fconsole.log(String(undefined));//unconsole.log(Number(undefined));//NaNconsole.log('---------------------NaN');//fconsole.log(Boolean(NaN));//fconsole.log(String(NaN));//nanconsole.log(Number(NaN));//nanconsole.log('---------------------Infinity');//fconsole.log(Boolean(+Infinity));//tconsole.log(Boolean(-Infinity));//tconsole.log(Number(-Infinity));//-Inconsole.log('---------------------false');//fconsole.log(Boolean(false));//fconsole.log(String(false));//fconsole.log(Number(false));//0console.log('---------------------空格字符');//fconsole.log(Boolean(' '));//tconsole.log(String(' '));//console.log(Number(' '));//0console.log('---------------------空字符');//fconsole.log(Boolean(''));//fconsole.log(String(''));//console.log(Number(''));//0console.log('---------------------字符0');//fconsole.log(Boolean('0'));//tconsole.log(String('0'));//0console.log(Number('0'));//0console.log('---------------------字符one');//fconsole.log(Boolean('one'));//tconsole.log(String('one'));//oneconsole.log(Number('one'));//NaNconsole.log('---------------------空数组');//fconsole.log(Boolean([]));//trueconsole.log(String([]));//console.log(Number([]));//0console.log('---------------------空对象');//fconsole.log(Boolean({a:1}));//trueconsole.log(String({a:1}));//object objectconsole.log(Number({a:1}));//NaNconsole.log('---------------------空函数');//fconsole.log(Boolean(fxx));//tconsole.log(String(fxx));//函数体console.log(Number(fxx));//NaN

console.log(null instanceof Object); //falseconsole.log(null === null); //trueconsole.log({} === {}); //falseconsole.log(null === {}); //false