nodejs中使用hashmap

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原文地址：

https://www.npmjs.com/package/hashmap

hashmap

Installation

Using npm:

$ npm install hashmap

Using bower:

$ bower install hashmap

You can download the last stable version from the releases page.

If you like risk, you can download the latest master version, it's usually stable.

To run the tests:

$ npm test

Description

This project provides a HashMap class that works both on Node.js and the browser. HashMap instances store key/value pairs allowing keys of any type.

Unlike regular objects, keys will not be stringified. For example numbers and strings won't be mixed, you can passDate's, RegExp's, DOM Elements, anything! (even null and undefined)

HashMap constructor overloads

• new HashMap() creates an empty hashmap
• new HashMap(map:HashMap) creates a hashmap with the key-value pairs of map
• new HashMap(key:*, value:*, key2:*, value2:*, ...) creates a hashmap with several key-value pairs

HashMap methods

• get(key:*) : * returns the value stored for that key.
• set(key:*, value:*) : HashMap stores a key-value pair
• multi(key:*, value:*, key2:*, value2:*, ...) : HashMap stores several key-value pairs
• copy(other:HashMap) : HashMap copies all key-value pairs from other to this instance
• has(key:*) : Boolean returns whether a key is set on the hashmap
• search(value:*) : * returns key under which given value is stored (null if not found)
• remove(key:*) : HashMap deletes a key-value pair by key
• type(key:*) : String returns the data type of the provided key (used internally)
• keys() : Array<*> returns an array with all the registered keys
• values() : Array<*> returns an array with all the values
• count() : Number returns the amount of key-value pairs
• clear() : HashMap removes all the key-value pairs on the hashmap
• clone() : HashMap creates a new hashmap with all the key-value pairs of the original
• hash(key:*) : String returns the stringified version of a key (used internally)
• forEach(function(value, key)) : HashMap iterates the pairs and calls the function for each one

Method chaining

All methods that don't return something, will return the HashMap instance to enable chaining.

Examples

Assume this for all examples below

var map = new HashMap();

If you're using this within Node, you first need to import the class

var HashMap = require('hashmap').HashMap;

Basic use case

map.set("some_key", "some value");map.get("some_key"); // --> "some value"

No stringification

map.set("1", "string one");map.set(1, "number one");map.get("1"); // --> "string one"

A regular Object used as a map would yield "number one"

Objects as keys

var key = {};var key2 = {};map.set(key, 123);map.set(key2, 321);map.get(key); // --> 123

A regular Object used as a map would yield 321

Iterating

map.set(1, "test 1");map.set(2, "test 2");map.set(3, "test 3");map.forEach(function(value, key) {    console.log(key + " : " + value);});

Method chaining

map    .set(1, "test 1")    .set(2, "test 2")    .set(3, "test 3")    .forEach(function(value, key) {        console.log(key + " : " + value);    });