Javacript中自定义的map.js 的方法
网络 2017-12-22 1216
js中没有map这个类，只能自己写一个。以下map.js和map-util.js都是自定义的map，任选其一就可以。你可以用它来像java里new Map()和put()、remove()、get()等方法。
map.js:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 | function Map() { var struct = function(key, value) { this.key = key; this.value = value; } var put = function(key, value){ for (var i = 0; i < this.arr.length; i++) { if ( this.arr[i].key === key ) { this.arr[i].value = value; return; } } this.arr[this.arr.length] = new struct(key, value); } var get = function(key) { for (var i = 0; i < this.arr.length; i++) { if ( this.arr[i].key === key ) { return this.arr[i].value; } } return null; } var remove = function(key) { var v; for (var i = 0; i < this.arr.length; i++) { v = this.arr.pop(); if ( v.key === key ) { continue; } this.arr.unshift(v); } } var size = function() { return this.arr.length; } var isEmpty = function() { return this.arr.length <= 0; } this.arr = new Array(); this.get = get; this.put = put; this.remove = remove; this.size = size; this.isEmpty = isEmpty; } |
map-util.js:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 | function Map() { this.elements = new Array(); var i; //获取MAP元素个数 this.size = function() { return this.elements.length; }; //判断MAP是否为空 this.isEmpty = function() { return (this.elements.length < 1); }; //删除MAP所有元素 this.clear = function() { this.elements = new Array(); }; //向MAP中增加元素（key, value) this.put = function(_key, _value) { this.elements.push( { key : _key, value : _value }); }; this.putFirst = function(_key, _value){ var tempList = this.elements; this.elements = new Array(); this.elements.push( { key : _key, value : _value }); for(var i=0;i<tempList.length;i++){ this.elements.push( tempList[i] ); } } //删除指定KEY的元素，成功返回True，失败返回False this.remove = function(_key) { var bln = false; try { for (i = 0; i < this.elements.length; i++) { if (this.elements[i].key == _key) { this.elements.splice(i, 1); return true; } } } catch (e) { bln = false; } return bln; }; //获取指定KEY的元素值VALUE，失败返回NULL this.get = function(_key) { try { for (i = 0; i < this.elements.length; i++) { if (this.elements[i].key == _key) { return this.elements[i].value; } } } catch (e) { return null; } }; //获取指定索引的元素（使用element.key，element.value获取KEY和VALUE），失败返回NULL this.element = function(_index) { if (_index < 0 || _index >= this.elements.length) { return null; } return this.elements[_index]; }; //判断MAP中是否含有指定KEY的元素 this.containsKey = function(_key) { var bln = false; try { for (i = 0; i < this.elements.length; i++) { if (this.elements[i].key == _key) { bln = true; } } } catch (e) { bln = false; } return bln; }; //判断MAP中是否含有指定VALUE的元素 this.containsValue = function(_value) { var bln = false; try { for (i = 0; i < this.elements.length; i++) { if (this.elements[i].value == _value) { bln = true; } } } catch (e) { bln = false; } return bln; }; //获取MAP中所有VALUE的数组（ARRAY） this.values = function() { var arr = new Array(); for (i = 0; i < this.elements.length; i++) { arr.push(this.elements[i].value); } return arr; }; //获取MAP中所有KEY的数组（ARRAY） this.keys = function() { var arr = new Array(); for (i = 0; i < this.elements.length; i++) { arr.push(this.elements[i].key); } return arr; }; } |
