什么是检查javascript中字符串集合中是否存在字符串的最快方法？

Question

In JavaScript, I need some data structure that can hold strings, and has a fast way to search if a string exists in it, and to insert a string in it.

I was planning to use an array, but I am currently using a dictionary where the key is the string and the value is just 'true' even through I don't use it.

I went with dictionary because I would think it would be something like an AVL tree, where the insert, delete and add are all O(log(n)) time. And the array would have an insert, delete, and search of O(n) time.

Is this right, or is there a better way?

Thanks

Answer 1

Use an object.

Add string:

obj[string] = true;

Check if string exists:

obj.hasOwnProperty(string);
// or simply
obj[string]

Answer 2

If you use an array.

You can use indexOf() to find the position. And splice() to insert a string into array object. Also if position does not matter, use push() .

This should be fast enough, it is in JS library.

EDIT:

Both indexOf() and splice() are linear.

Answer 3

var stringStore = {};

stringStore['sample-string-1'] = 'sample-string-1';

stringStore['sample-string-2'] = 'sample-string-2';

if (stringStore['sample-string-2'] ) console.log("string 2 exists"); else console.log("string 2 doesn't exists");

if (stringStore['sample-string-3'] ) console.log("string 3 exists"); else console.log("string3 doesn't exists");