javascript实现简单的Map示例介绍

复制代码 代码如下:

  /*

  * MAP对象,实现MAP功能

  *

  * 接口:

  * size() 获取MAP元素个数

  * isEmpty() 判断MAP是否为空

  * clear() 删除MAP所有元素

  * put(key, value) 向MAP中增加元素(key, value)

  * remove(key) 删除指定KEY的元素,成功返回True,失败返回False

  * get(key) 获取指定KEY的元素值VALUE,失败返回NULL

  * element(index) 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

  * containsKey(key) 判断MAP中是否含有指定KEY的元素

  * containsValue(value) 判断MAP中是否含有指定VALUE的元素

  * values() 获取MAP中所有VALUE的数组(ARRAY)

  * keys() 获取MAP中所有KEY的数组(ARRAY)

  *

  * 例子:

  * var map = new Map();

  *

  * map.put("key", "value");

  * var val = map.get("key")

  * ……

  *

  */

  function Map() {

  this.elements = new Array();

  //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

  });

  };

  //删除指定KEY的元素,成功返回True,失败返回False

  this.removeByKey = 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;

  };

  //删除指定VALUE的元素,成功返回True,失败返回False

  this.removeByValue = function(_value) {//removeByValueAndKey

  var bln = false;

  try {

  for (i = 0; i < this.elements.length; i++) {

  if (this.elements[i].value == _value) {

  this.elements.splice(i, 1);

  return true;

  }

  }

  } catch (e) {

  bln = false;

  }

  return bln;

  };

  //删除指定VALUE的元素,成功返回True,失败返回False

  this.removeByValueAndKey = function(_key,_value) {

  var bln = false;

  try {

  for (i = 0; i < this.elements.length; i++) {

  if (this.elements[i].value == _value && 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 false;

  }

  return false;

  };

  //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;

  };

  //判断MAP中是否含有指定VALUE的元素

  this.containsObj = function(_key,_value) {

  var bln = false;

  try {

  for (i = 0; i < this.elements.length; i++) {

  if (this.elements[i].value == _value && this.elements[i].key == _key) {

  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VALUE的数组(ARRAY)

  this.valuesByKey = function(_key) {

  var arr = new Array();

  for (i = 0; i < this.elements.length; i++) {

  if (this.elements[i].key == _key) {

  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;

  };

  //获取key通过value

  this.keysByValue = function(_value) {

  var arr = new Array();

  for (i = 0; i < this.elements.length; i++) {

  if(_value == this.elements[i].value){

  arr.push(this.elements[i].key);

  }

  }

  return arr;

  };

  //获取MAP中所有KEY的数组(ARRAY)

  this.keysRemoveDuplicate = function() {

  var arr = new Array();

  for (i = 0; i < this.elements.length; i++) {

  var flag = true;

  for(var j=0;j<arr.length;j++){

  if(arr[j] == this.elements[i].key){

  flag = false;

  break;

  }

  }

  if(flag){

  arr.push(this.elements[i].key);

  }

  }

  return arr;

  };

  }