Node.js - 模块导出静态变量

Question

I'm attempting to export a module that should store a hashtable of given information so that another call to access that information can be checked for existence in the hashtable, and if found, return the value in the hashtable.

I am having trouble getting the hashtable in the export to remain consistent throughout the app as a singleton/static/global variable.

Here's what I have:

var Randomize = {

  hashTable: [],
  randomize:  function(rows) {

    var randomized = [];
    for(var i in rows) {
      //check if exists in hashtable, use values accordingly
    }
    return randomized;
  }

};

module.exports = Randomize;

And when I try to access it with:

var randomize = require('randomize');
/* ... */
console.log(randomize.randomize(rows))

It creates a new hashtable for each instance. How can I make it so that it reuses the same instance of hashtable?

Answer 1

Your hashtable might be in the wrong scope - it's possibly being clobbered with each require . Try this instead:

var hashTable = [];

var Randomize = {

  hashTable: hashTable,
  randomize:  function(rows) {

    var randomized = [];
    for(var i in rows) {
      //check if exists in hashtable, use values accordingly
    }
    return randomized;
  }
};

module.exports = Randomize;