1. 嚴格相等 ===（嚴格相等比較的是兩個值是否相等，兩個被比較的值在比較前都不進行隱式轉換（即不轉換數據類型），所以當兩個值當數據類型不一致時，是不相等的）
console.log(0 === 0)// true
console.log(+0 === -0)// true
console.log(0 === -0)// true
console.log(0 === +0)// true
console.log(0 === new Number(0))// false
console.log(new Number(0) === new Number(0))// false 可以使用typeof查看兩者的區別
console.log(Number(0) === Number(0))// true
console.log(0 === '0')// false
console.log(0 === '')// false
console.log(0 === null)// false
console.log(0 === undefined)// false
console.log(0 === new String())// false
console.log('0' === '0')// true
console.log('0' === new String(0))// false
console.log(new String(0) === new String(0))// false
console.log(String(0) === String(0))// true
console.log(null === null)// true
console.log(null === undefined)// false
console.log(undefined === undefined)// true
console.log(NaN === NaN)// false
console.log(0 === false)// false
console.log(false === false)// true
console.log({} === {})// false
console.log({} === new Object())// false
console.log(new Object() === new Object())// false
console.log(Object() === Object())// false
console.log([] === [])// false
console.log([] === new Array())// false
console.log(new Array() == new Array())// false
console.log(Array() == Array())// false
console.log(Symbol() === Symbol())// false (ES6語法)
console.log(Symbol('test') === Symbol('test'))// false (ES6語法)
建議不要使用new 新建對象
2. 非嚴格相等 ==（非嚴格相等比較是兩個值是否相等，兩個被比較的值，在被比較前會被轉為相同的數據類型）
console.log(0 == 0)// true
console.log(+0 == -0)// true
console.log(0 == -0)// true
console.log(0 == +0)// true
console.log(0 == new Number(0))// true
console.log(new Number(0) == new Number(0))// false
console.log(Number(0) === Number(0))// true
console.log(0 == '0')// true
console.log(0 == '')// true
console.log(0 == null)// false
console.log(0 == undefined)// false
console.log(0 == new String())// true
console.log('0' == '0')// true
console.log('0' == new String(0))// true
console.log(new String(0) == new String(0))// false
console.log(String(0) == String(0))// true
console.log(null == null)// true
console.log(null == undefined)// true
console.log(undefined == undefined)// true
console.log(NaN == NaN)// false
console.log(0 == false)// true
console.log(false == false)// true
console.log({} == {})// false
console.log({} == new Object())// false
console.log(new Object() == new Object())// false
console.log(Object() == Object())// false
console.log([] == [])// false
console.log([] == new Array())// false
console.log(new Array() == new Array())// false
console.log(Array() == Array())// false
console.log(Symbol() == Symbol())// false (ES6語法)
console.log(Symbol('test') == Symbol('test'))// false (ES6語法)
3. Object.is() (ES6語法，用來比較兩個值是否嚴格相等，與嚴格相等的行為基本一致，不同之處：+0不等於-0；NaN等於NaN)
console.log(Object.is(+0, -0))// false
console.log(Object.is(0, -0))// false
console.log(Object.is(+0, 0))// true
console.log(Object.is(NaN, NaN))// true