如何避免 <thead> 和 <tbody> 之间分页

Question

我正在尝试制作一个带有一些相当长的表格的可打印文档。有时页面正好在表头和数据之间结束，这使得阅读变得更加困难。

例子

我怎样才能防止这种情况发生呢？

我尝试使用以下 CSS，但没有帮助。

@media print {
        h1, h2, h3, thead, thead>tr {
            page-break-after: avoid;
            page-break-inside: avoid;
        }

        tbody {
            page-break-before: avoid;
        }

        /* I would also like to not have page breaks within first five rows */
        tbody:nth-child(-n+5) {    
            page-break-before: avoid;
        }
}

表结构：

<table border="1" cellspacing="0" cellpadding="3">
    <thead>
    <tr>
        <th rowspan="2">Metric</th>
        <th colspan="3">Type 1</th>
        <th colspan="3">Type 2<th>
    </tr>
    <tr>
        <th>Initial</th>
        <th>Final</th>
        <th>Difference</th>
        <th>Initial</th>
        <th>Final</th>
        <th>Difference</th>
    </tr>
    </thead>
    <tbody>
    <tr>
        <td>Dataset1</td>
        <td>*DATA*</td>
        ...
    </tr>
    </tbody>
</table>

Answer 1

将分页符应用于您的块级伪元素，tbody而不是直接将其应用于tbody. 这是工作演示

您必须仔细定义页面上下文以及适当的边距和尺寸以适合您的用例。

table, th, td { border: 1px solid gray; border-collapse: collapse; }
th, td { padding: 8px; }
tbody:first-of-type { background-color: #eee; }

@page {
    size: A4;
    margin: 0;
}
@media print {
    html, body {
        width: 210mm;
        height: 297mm;
    }
    tbody::after {
        content: ''; display: block;
        page-break-after: always;
        page-break-inside: avoid;
        page-break-before: avoid;        
    }
    
  
}

<div> 
    <a href="#" onClick="window.print();">Print</a>
</div>
<hr />
<table>
    <thead>
		<tr>
			<th>Head 1</th>
			<th>Head 2</th>
			<th>Head 3</th>
		</tr>
    </thead>
	<tbody>
		<tr>
			<td>Row 1 Cell 1</td>
			<td>Row 1 Cell 2</td>
			<td>Row 1 Cell 3</td>
		</tr>
		<tr>
			<td>Row 2 Cell 1</td>
			<td>Row 2 Cell 2</td>
			<td>Row 2 Cell 3</td>
		</tr>
	</tbody>
	<tbody>
		<tr>
			<td>Row 3 Cell 1</td>
			<td>Row 3 Cell 2</td>
			<td>Row 3 Cell 3</td>
		</tr>
		<tr>
			<td>Row 4 Cell 1</td>
			<td>Row 4 Cell 2</td>
			<td>Row 4 Cell 3</td>
		</tr>
	</tbody>
    <tfoot>
		<tr>
			<th>Foot 1</th>
			<th>Foot 2</th>
			<th>Foot 3</th>
		</tr>	
    </tfoot>
</table>