a simple hashtable implement with js.

hashtable.js

class HashTable {
  constructor (size = 16) {
    this.bucket = [];
    this.bucketSize = size;
  }

  getHash(str) {
    try {
      return str.split('').map(function(c) {
        return c.charCodeAt();
      }).reduce(function (a, b) {
        return a + b;
      });
    }catch (err) {
      return 0;
    }
  }

  set(key, value) {
    let hash = this.getHash(key);
    let index = hash % this.bucketSize;
    if(this.bucket[index] === undefined) {
      this.bucket[index] = [[key, value]];
    }else {
      for (let pair of this.bucket[index]) {
        if(pair[0] === key) {
          pair[1] = value
          return;
        }
      }

      this.bucket[index].push([key, value]);
    }
  }

  get(key) {
    let hash = this.getHash(key);
    let index = hash % this.bucketSize;
    if(this.bucket[index] === undefined) {
      return undefined
    }else {
      for (let pair of this.bucket[index]) {
        if(pair[0] === key) {
          return pair[1]
        }
      }

      return undefined;
    }
  }
}