Question

查看第一个代码：

 var count = 0;
 (function addLinks() {
   var count = 0;//this count var is increasing

   for (var i = 0, link; i < 5; i++) {
     link = document.createElement("a");
     link.innerHTML = "Link " + i;

     link.onclick = function () {
       count++;
       alert(count);
     };

     document.body.appendChild(link);
   }
 })();

单击链接后，每个链接元素的计数器变量都会继续增加。这是预期的结果。

第二

var count = 0;
$("p").each(function () {
  var $thisParagraph = $(this);
  var count = 0;//this count var is increasing too.so what is different between them .They both are declared within the scope in which closure was declared

  $thisParagraph.click(function () {
    count++;
    $thisParagraph.find("span").text('clicks: ' + count);
    $thisParagraph.toggleClass("highlight", count % 3 == 0);
  });
});

此处闭包功能未按预期工作。每次点击段落元素时，计数器var都会增加，但点击第二段元素时不显示该增量？这是什么原因？为什么会这样？每个段落元素的count变量都没有增加。

Answer 1

你的意思是：

var count = 0;
$("p").each(function() {
   var $thisParagraph = $(this);
   //var count = 0; //removed this count, as it re-inits count to 0
   $thisParagraph.click(function() {
   count++;
   $thisParagraph.find("span").text('clicks: ' + count);
   $thisParagraph.toggleClass("highlight", count % 3 == 0);
  });
});

javascript关闭不能正常工作

1 个答案: