javascript - 搜索 javascript 对象数组的更有效方法？

Question

不确定发布规则，但我会告诉你这是this one的重复问题，但我想问这是否是“最佳实践”方法？

Answer 1

这是执行此操作的直接方法。如果您需要多次快速访问，您应该创建一个以您要搜索的属性名称为键的 map 。

这是一个接受数组并构建键控映射的函数。它不是通用的，但您应该能够对其进行修改以供自己使用。

/**
 * Given an array and a property name to key by, returns a map that is keyed by each array element's chosen property
 * This method supports nested lists
 * Sample input: list = [{a: 1, b:2}, {a:5, b:7}, [{a:8, b:6}, {a:7, b:7}]]; prop = 'a'
 * Sample output: {'1': {a: 1, b:2}, '5': {a:5, b:7}, '8': {a:8, b:6}, '7':{a:7, b:7}}
 * @param {object[]} list of objects to be transformed into a keyed object
 * @param {string} keyByProp The name of the property to key by
 * @return {object} Map keyed by the given property's values
 */
function mapFromArray (list , keyByProp) {
  var map = {};
  for (var i=0, item; item = list[i]; i++) {
    if (item instanceof Array) {
      // Ext.apply just copies all properties from one object to another,
      // you'll have to use something else. this is only required to support nested arrays.
      Ext.apply(map, mapFromArray(item, keyByProp));
    } else {
      map[item[keyByProp]] = item;
    }
  }
  return map;
};