如何自定义 jquery 数据表导出 PDF？

Question

我已经修改了数据表上的一个单元格以显示一个彩色 div，它是一个取决于分数的渐变

{
"data": "fert_percent",
"autoWidth": true,
"searchable": true,
"render": function (data, type, row, meta)
{
var ret = "<div class='col' style='background-color: lawngreen;'><div class='col' style='background-color: red; opacity: " + (data / 100) + ";'>&nbsp;</div></div>";
return ret;
}
},

代码可以正常查看表格，但如果我导出为 PDF，则单元格为空。

如何让导出的 PDF 显示修改后的单元格？

Answer 1

pdfMake 库不支持背景颜色的不透明度，它仅适用于字体。如果您想知道为什么会这样，那是因为 PDF 格式与 CSS 标准无关。

也就是说，如果在 DataTables 将其发送到文件生成器之前更新 pdfMake 文档，则可以导出不同的颜色：

（注意：我没有费心将果岭放入 DataTable 版本，仅导出 PDF）

$(document).ready(function() {

  $('#example').DataTable({
    columns: [{
        "data": "name"
      },
      {
        "data": "position"
      },
      {
        "data": "office"
      },
      {
        "data": "age"
      },
      {
        "data": "start_date"
      },
      {
        "data": "salary"
      }
    ],
    dom: 'Bfrtip',
    buttons: [{
      extend: 'pdfHtml5',
      text: 'PDF with cell background colour',
      customize: function(doc) { // set the cell colours for the PDF
        //console.log(doc); // useful if you want to see what the doc object contains

        // you can set generate styles like this if you want
        //doc.styles["Opac10"] = { opacity: "0.1"};

        let table = doc.content[1].table.body;

        for (i = 1; i < table.length; i++) // skip table header row (i = 0)
        {
          table[i][3].text = " "; // couldn't be bothered clearing the Age column sample data above :)
          table[i][3].fillColor = "#00" + Math.round((i / 9) * 255).toString(16) + "00"; // ( divided by 9 since 9 rows in my example)

          
          if (table[i][2].text == 'Tokyo') {
            table[i][2].fillColor = '#fbed1d'; // yellow
            //table[i][2].style = 'Opac10'; // Here's how you can refer to styles from above. Note: opacity only applies to the font, not the background colour in the pdf table cell!!     
          }
        }
      }
    }],
    rowCallback: function(row, data, index) { // sets the cell colours for DataTables
      if (data.office == "Tokyo") {
        $('td:eq(2)', row).css('background-color', '#fbed1d'); // yellow
      }
    }
  });
});

<link rel="stylesheet" type="text/css" href="https://cdn.datatables.net/1.11.4/css/jquery.dataTables.min.css">
<link rel="stylesheet" type="text/css" href="https://cdn.datatables.net/buttons/2.2.2/css/buttons.dataTables.min.css">

<script type="text/javascript" language="javascript" src="https://code.jquery.com/jquery-3.5.1.js"></script>
<script type="text/javascript" language="javascript" src="https://cdn.datatables.net/1.11.4/js/jquery.dataTables.min.js"></script>
<script type="text/javascript" language="javascript" src="https://cdn.datatables.net/buttons/2.2.2/js/dataTables.buttons.min.js"></script>
<script type="text/javascript" language="javascript" src="https://cdnjs.cloudflare.com/ajax/libs/jszip/3.1.3/jszip.min.js"></script>
<script type="text/javascript" language="javascript" src="https://cdnjs.cloudflare.com/ajax/libs/pdfmake/0.1.53/pdfmake.min.js"></script>
<script type="text/javascript" language="javascript" src="https://cdnjs.cloudflare.com/ajax/libs/pdfmake/0.1.53/vfs_fonts.js"></script>
<script type="text/javascript" language="javascript" src="https://cdn.datatables.net/buttons/2.2.2/js/buttons.html5.min.js"></script>

<table id="example" class="display" style="width:100%">
  <thead>
    <tr>
      <th>Name</th>
      <th>Position</th>
      <th>Office</th>
      <th>Age</th>
      <th>Start date</th>
      <th>Salary</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td>Tiger Nixon</td>
      <td>System Architect</td>
      <td>Edinburgh</td>
      <td>61</td>
      <td>2011/04/25</td>
      <td>320800</td>
    </tr>
    <tr>
      <td>Garrett Winters</td>
      <td>Accountant</td>
      <td>Tokyo</td>
      <td>63</td>
      <td>2011/07/25</td>
      <td>170750</td>
    </tr>
    <tr>
      <td>Ashton Cox</td>
      <td>Junior Technical Author</td>
      <td>San Francisco</td>
      <td>66</td>
      <td>2009/01/12</td>
      <td>86000</td>
    </tr>
    <tr>
      <td>Cedric Kelly</td>
      <td>Senior Javascript Developer</td>
      <td>Edinburgh</td>
      <td>22</td>
      <td>2012/03/29</td>
      <td>433060</td>
    </tr>
    <tr>
      <td>Airi Satou</td>
      <td>Accountant</td>
      <td>Tokyo</td>
      <td>33</td>
      <td>2008/11/28</td>
      <td>162700</td>
    </tr>
    <tr>
      <td>Brielle Williamson</td>
      <td>Integration Specialist</td>
      <td>New York</td>
      <td>61</td>
      <td>2012/12/02</td>
      <td>372000</td>
    </tr>
    <tr>
      <td>Herrod Chandler</td>
      <td>Sales Assistant</td>
      <td>San Francisco</td>
      <td>59</td>
      <td>2012/08/06</td>
      <td>137500</td>
    </tr>
    <tr>
      <td>Rhona Davidson</td>
      <td>Integration Specialist</td>
      <td>Tokyo</td>
      <td>55</td>
      <td>2010/10/14</td>
      <td>327900</td>
    </tr>
    <tr>
      <td>Donna Snider</td>
      <td>Customer Support</td>
      <td>New York</td>
      <td>27</td>
      <td>2011/01/25</td>
      <td>112000</td>
    </tr>
  </tbody>
  <tfoot>
    <tr>
      <th>Name</th>
      <th>Position</th>
      <th>Office</th>
      <th>Age</th>
      <th>Start date</th>
      <th>Salary</th>
    </tr>
  </tfoot>
</table>