Question

虽然他们以自己的方式截然不同，但他们往往服务于类似的目的。简单地说，我想知道两者中哪一个比另一个更高效？一般来说，比另一个更优先，还是个人偏好？

object(AppBundle\Entity\Item)[560]
  private 'id' => int 23
  private 'accountId' => int 1
  private 'itemType' => null
  private 'fieldCount' => int 4
  private 'ver' => int 1451940837
  private 'title' => string 'New Item' (length=8)
  protected 'fields' => 
    array (size=0)
      empty
  protected 'itemValues' => 
    array (size=0)
      empty
  protected 'cacheValues' => 
    array (size=0)
      empty
  protected 'logger' => null
  protected 'itemsRepository' => null
  protected 'itemValuesRepository' => null
  protected 'fieldsRepository' => null
  protected 'loaded' => boolean false
  protected 'changeCount' => int 0
object(AppBundle\Entity\ItemType)[507]
  private 'id' => int 31
  private 'accountId' => int 1
  private 'name' => string 'task' (length=4)
  private 'pluralName' => string 'tasks' (length=5)
  private 'label' => string 'Task' (length=4)
  private 'pluralLabel' => string 'Tasks' (length=5)
  private 'areUsers' => boolean true
  private 'ownUsers' => boolean false

$("div").each(function(index, element) {
  this.id
});

Answer 1

element参考

$("div").each(function(index, element) {
  element.id
});

似乎是最快的＆＃34; 。保证金很小。最后一次测试尝试了铬49 element.id：54,990，this.id：5485。结果可能因浏览器或使用的浏览器版本而异。或者，正如@ RyanO＆＃39; Hara简明扼要地指出

一般来说无关紧要

jsperf http://jsperf.com/this-vs-currentvalue-of-an-iterator-function

这与迭代器函数的currentValue有关

1 个答案: