diff --git "a/39\351\231\206\345\273\272\351\224\213/2022-10-27\347\254\254\345\205\253\346\254\241\344\275\234\344\270\232\350\275\254\345\257\271\350\261\241/2022-10-27\344\275\234\344\270\232.html" "b/39\351\231\206\345\273\272\351\224\213/2022-10-27\347\254\254\345\205\253\346\254\241\344\275\234\344\270\232\350\275\254\345\257\271\350\261\241/2022-10-27\344\275\234\344\270\232.html" new file mode 100644 index 0000000000000000000000000000000000000000..57dbc4d18158d6908d8143a6ff76d503f1846c1d --- /dev/null +++ "b/39\351\231\206\345\273\272\351\224\213/2022-10-27\347\254\254\345\205\253\346\254\241\344\275\234\344\270\232\350\275\254\345\257\271\350\261\241/2022-10-27\344\275\234\344\270\232.html" @@ -0,0 +1,28 @@ + + + + + + + Document + + + + + \ No newline at end of file diff --git "a/39\351\231\206\345\273\272\351\224\213/2022-10-27\347\254\254\345\205\253\346\254\241\344\275\234\344\270\232\350\275\254\345\257\271\350\261\241/2022-10-27\347\254\224\350\256\260.md" "b/39\351\231\206\345\273\272\351\224\213/2022-10-27\347\254\254\345\205\253\346\254\241\344\275\234\344\270\232\350\275\254\345\257\271\350\261\241/2022-10-27\347\254\224\350\256\260.md" new file mode 100644 index 0000000000000000000000000000000000000000..c288d9aa10e1307a8f645a9a8992cf055a45cdce --- /dev/null +++ "b/39\351\231\206\345\273\272\351\224\213/2022-10-27\347\254\254\345\205\253\346\254\241\344\275\234\344\270\232\350\275\254\345\257\271\350\261\241/2022-10-27\347\254\224\350\256\260.md" @@ -0,0 +1,109 @@ + 引用型:function, array, obj, + ES6: map set + Map:键值对,类似于对象 + var name = 'keys' + var ma = new Map(); + console.log(typeof ma); //ma是对象 + ma.set(5, 'Zoe'); + console.log(ma); + ma.set(name, '张三'); //返回增加后的map + console.log(result); + + delete:map.delete(key):根据键删除,如果找到该键,那就删除成功,返回true,否则返回false. + var result = ma.delete(5); + console.log(result); + var re = ma.clear() //清空数据,无返回值 + console.log(re); + + 改 + ma.set(5, 'Joe') + + 查 + //keys + for (let e of ma.keys()){ + console.log(e); + } + + //values + for (let e of ma.values()){ + console.log(e); + } + //entries + for (let e of ma.entries()){ + console.log(e); + } + //map + for(let e of map){ + console.log(e); + } + + obj:不可迭代 let[k,v] = [键,值] + for(let[k,v] of ma){ + console.log(k,v); + } + + + + //不管是+0,0,-0,当成了同一个键, + map.set(-0, 123); + map.get(+0); + + + map转数组 [] + const arr = [...map] + const arr = [] + for(let e of map.entries()){ + arr.push(e) + } + + + 数组转map + const arr = [['name', 'zoe'], ['age', 18]] + var map = new Map([ + ['name', 'zoe'], ['age', 18] + ]) + + map转对象 + const map=new Map() + map.set('name','Zoe').set('age',16).set('gender','male') + var obj = {} + for(let [k,y] of map){ + obj[k]=y + } + + 对象转map + + + + + + set:(装不重复的元素)数组 + var set = new Set(); + set.add(5); + //set,map:+0,-0,0 :同一个元素 NaN + set.add(+0); + set.add(-0); + set.add(null); + set.add(NaN); + set.add(NaN); + console.log(set.size); //4 + console.log(Set.prototype); + //keys + for(let e of set.keys()){ + // console.log(e); + // } + + //values + for(let e of set.values()){ + console.log(e); + } + //entries + for(let e of set.entries()){ + console.log(e); + } + ste + for (const e of set) { + console.log(e); + } + + WeakSet WeakMap:弱引用(直接回收),强引用(不会强制回收)