jquery - 选择奇数和偶数元素

Question

我想要样式odd和even tr元素与我的表格不同。

这是我的代码:

jsFiddle

/*
Create a one-liner code to add the class ‘odd’ to an odd number row and the class ‘even’ to an even number row
Hint: Use the nth-child selector and the end() function
*/

table,
tr,
td {
  border-collapse: collapse;
  border: 1px solid #000;
}
table {
  width: 100%;
}
tr.odd {
  background: rgba(0, 255, 0, 0.1);
}
tr.even {
  background: rgba(0, 0, 0, 0.1);
}

<table>
  <tr>
    <td>odd</td>
    <td>odd</td>
  </tr>
  <tr>
    <td>even</td>
    <td>even</td>
  </tr>
  <tr>
    <td>odd</td>
    <td>odd</td>
  </tr>
  <tr>
    <td>even</td>
    <td>even</td>
  </tr>
  <tr>
    <td>odd</td>
    <td>odd</td>
  </tr>
</table>

提示:使用第 n 个子级选择器和 end() 函数

Answer 1

如果你有jQuery，你可以使用:odd和 :even选择器

$('tr:odd').addClass('odd');
$('tr:even').addClass('even');

Demo

$('tr:odd').addClass('odd');
$('tr:even').addClass('even');

table,
tr,
td {
  border-collapse: collapse;
  border: 1px solid #000;
}
table {
  width: 100%;
}
tr.odd {
  background: rgba(0, 255, 0, 0.1);
}
tr.even {
  background: rgba(0, 0, 0, 0.1);
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.10.0/jquery.min.js"></script>
<table>
  <tr>
    <td>odd</td>
    <td>odd</td>
  </tr>
  <tr>
    <td>even</td>
    <td>even</td>
  </tr>
  <tr>
    <td>odd</td>
    <td>odd</td>
  </tr>
  <tr>
    <td>even</td>
    <td>even</td>
  </tr>
  <tr>
    <td>odd</td>
    <td>odd</td>
  </tr>
</table>

仅使用 CSS

您还可以使用 CSS nth-child 选择器选择奇数和偶数元素。

table,
tr,
td {
  border-collapse: collapse;
  border: 1px solid #000;
}
table {
  width: 100%;
}
tr:nth-child(2n) {
  background: rgba(0, 255, 0, 0.1);
}
tr:nth-child(2n + 1) {
  background: rgba(0, 0, 0, 0.1);
}

<table>
  <tr>
    <td>odd</td>
    <td>odd</td>
  </tr>
  <tr>
    <td>even</td>
    <td>even</td>
  </tr>
  <tr>
    <td>odd</td>
    <td>odd</td>
  </tr>
  <tr>
    <td>even</td>
    <td>even</td>
  </tr>
  <tr>
    <td>odd</td>
    <td>odd</td>
  </tr>
</table>