jquery 每个函数 -> class 名称是 "undefined" for $(".row > div").each(function(i) {};

Question

我收到以下代码的 "myval: undefined" 消息。我想知道如何获得当前 class 的 class anme?

这是我的功能：

$(".row > div").each(function(i) {
            var myval = $(this).attr('class');
             console.log ("myval: " + myval)
});

HTML:

<div class="row">
 <div class="item1">item</div>
 <div class="item2">item</div>
</div>

<div class="row">
 <div class="item3">item</div>
 <div class="item4">item</div>
</div>

<div class="row">
 <div class="item5">item</div>
 <div class="item6">item</div>
</div>

etc.

Answer 1

我看不出您的代码有任何问题，请检查您是否正确包含了 jQuery 库。

此处示例： http://jsbin.com/rutameg/edit?html,js,console,output

$(".row > div").each( function() { // Removed i as not in use
            var myval = $(this).attr('class');
             console.log ("myval: " + myval)
});

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title>JS Bin</title>
</head>
<body>
  
  
  
  <div class="row">
 <div class="item1">item 1</div>
 <div class="item2">item 2</div>
</div>

<div class="row">
 <div class="item3">item 3</div>
 <div class="item4">item 4</div>
</div>

<div class="row">
 <div class="item5">item 5</div>
 <div class="item6">item 6</div>
<script src="https://code.jquery.com/jquery-3.1.0.js"></script>
</div>

</body>
</html>

Answer 2

你的代码方式正确，结果符合预期

$(".row > div").each( function(i) { // Removed i as not in use
            var myval = $(this).attr('class');
             console.log ("myval: " + myval)
});

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title>JS Bin</title>
</head>
<body>
  
  
  
  <div class="row">
 <div class="item1">item 1</div>
 <div class="item2">item 2</div>
</div>

<div class="row">
 <div class="item3">item 3</div>
 <div class="item4">item 4</div>
</div>

<div class="row">
 <div class="item5">item 5</div>
 <div class="item6">item 6</div>
<script src="https://code.jquery.com/jquery-3.1.0.js"></script>
</div>

</body>
</html>

jquery 每个函数 -> class 名称是 "undefined" for $(".row > div").each(function(i) {};

jquery each function -> class name is "undefined" for $(".row > div").each(function(i) {};

variables

each

jquery

undefined