数据表完全渲染后调用rowGroup答案

【问题标题】：Invoking rowGroup after the datatable is rendered completely数据表完全渲染后调用rowGroup
【发布时间】：2018-07-22 08:14:30
【问题描述】：

我有以下代码来进行行分组以及平均工资：

Link to JSFIDDLE

$(document).ready(function() {
  $('#example').DataTable({
    order: [
      [2, 'asc']
    ],
    rowsGroup: [2],
    rowGroup: {
      startRender: null,
      endRender: function(rows, group) {

        var salaryAvg = rows
          .data()
          .pluck(5)
          .reduce(function(a, b) {
            return a + b.replace(/[^\d]/g, '') * 1;
          }, 0) / rows.count();
        salaryAvg = $.fn.dataTable.render.number(',', '.', 0, '$').display(salaryAvg);

        var ageAvg = rows
          .data()
          .pluck(3)
          .reduce(function(a, b) {
            return a + b * 1;
          }, 0) / rows.count();
        console.log(salaryAvg);
        console.log(ageAvg);
        return $('<tr/>')
          .append('<td colspan="3">Averages for ' + group + '</td>')
          .append('<td>' + ageAvg.toFixed(0) + '</td>')
          .append('<td/>')
          .append('<td>' + salaryAvg + '</td>');
      },
      dataSrc: 2
    }
  });
});

<script src="https://code.jquery.com/jquery-3.3.1.js"></script>
<script src="https://cdn.datatables.net/1.10.19/js/jquery.dataTables.min.js"></script>
<script src="https://cdn.datatables.net/rowgroup/1.0.4/js/dataTables.rowGroup.min.js"></script>
<link rel="stylesheet" href="https://cdn.datatables.net/1.10.19/css/jquery.dataTables.min.css" />
<link rel="stylesheet" href="https://cdn.datatables.net/rowgroup/1.0.4/css/rowGroup.dataTables.min.css" />
<script src="https://cdn.rawgit.com/ashl1/datatables-rowsgroup/v1.0.0/dataTables.rowsGroup.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>$320,800</td>
    </tr>
    <tr>
      <td>Garrett Winters</td>
      <td>Accountant</td>
      <td>Tokyo</td>
      <td>63</td>
      <td>2011/07/25</td>
      <td>$170,750</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>$86,000</td>
    </tr>
    <tr>
      <td>Cedric Kelly</td>
      <td>Senior Javascript Developer</td>
      <td>Edinburgh</td>
      <td>22</td>
      <td>2012/03/29</td>
      <td>$433,060</td>
    </tr>
    <tr>
      <td>Airi Satou</td>
      <td>Accountant</td>
      <td>Tokyo</td>
      <td>33</td>
      <td>2008/11/28</td>
      <td>$162,700</td>
    </tr>
    <tr>
      <td>Brielle Williamson</td>
      <td>Integration Specialist</td>
      <td>New York</td>
      <td>61</td>
      <td>2012/12/02</td>
      <td>$372,000</td>
    </tr>
    <tr>
      <td>Herrod Chandler</td>
      <td>Sales Assistant</td>
      <td>San Francisco</td>
      <td>59</td>
      <td>2012/08/06</td>
      <td>$137,500</td>
    </tr>
    <tr>
      <td>Rhona Davidson</td>
      <td>Integration Specialist</td>
      <td>Tokyo</td>
      <td>55</td>
      <td>2010/10/14</td>
      <td>$327,900</td>
    </tr>
    <tr>
      <td>Colleen Hurst</td>
      <td>Javascript Developer</td>
      <td>San Francisco</td>
      <td>39</td>
      <td>2009/09/15</td>
      <td>$205,500</td>
    </tr>
    <tr>
      <td>Sonya Frost</td>
      <td>Software Engineer</td>
      <td>Edinburgh</td>
      <td>23</td>
      <td>2008/12/13</td>
      <td>$103,600</td>
    </tr>
    <tr>
      <td>Jena Gaines</td>
      <td>Office Manager</td>
      <td>London</td>
      <td>30</td>
      <td>2008/12/19</td>
      <td>$90,560</td>
    </tr>
    <tr>
      <td>Quinn Flynn</td>
      <td>Support Lead</td>
      <td>Edinburgh</td>
      <td>22</td>
      <td>2013/03/03</td>
      <td>$342,000</td>
    </tr>
    <tr>
      <td>Charde Marshall</td>
      <td>Regional Director</td>
      <td>San Francisco</td>
      <td>36</td>
      <td>2008/10/16</td>
      <td>$470,600</td>
    </tr>
    <tr>
      <td>Haley Kennedy</td>
      <td>Senior Marketing Designer</td>
      <td>London</td>
      <td>43</td>
      <td>2012/12/18</td>
      <td>$313,500</td>
    </tr>
    <tr>
      <td>Tatyana Fitzpatrick</td>
      <td>Regional Director</td>
      <td>London</td>
      <td>19</td>
      <td>2010/03/17</td>
      <td>$385,750</td>
    </tr>
    <tr>
      <td>Michael Silva</td>
      <td>Marketing Designer</td>
      <td>London</td>
      <td>66</td>
      <td>2012/11/27</td>
      <td>$198,500</td>
    </tr>
    <tr>
      <td>Paul Byrd</td>
      <td>Chief Financial Officer (CFO)</td>
      <td>New York</td>
      <td>64</td>
      <td>2010/06/09</td>
      <td>$725,000</td>
    </tr>
    <tr>
      <td>Gloria Little</td>
      <td>Systems Administrator</td>
      <td>New York</td>
      <td>59</td>
      <td>2009/04/10</td>
      <td>$237,500</td>
    </tr>
    <tr>
      <td>Bradley Greer</td>
      <td>Software Engineer</td>
      <td>London</td>
      <td>41</td>
      <td>2012/10/13</td>
      <td>$132,000</td>
    </tr>
    <tr>
      <td>Dai Rios</td>
      <td>Personnel Lead</td>
      <td>Edinburgh</td>
      <td>35</td>
      <td>2012/09/26</td>
      <td>$217,500</td>
    </tr>
    <tr>
      <td>Jenette Caldwell</td>
      <td>Development Lead</td>
      <td>New York</td>
      <td>30</td>
      <td>2011/09/03</td>
      <td>$345,000</td>
    </tr>
    <tr>
      <td>Yuri Berry</td>
      <td>Chief Marketing Officer (CMO)</td>
      <td>New York</td>
      <td>40</td>
      <td>2009/06/25</td>
      <td>$675,000</td>
    </tr>
    <tr>
      <td>Caesar Vance</td>
      <td>Pre-Sales Support</td>
      <td>New York</td>
      <td>21</td>
      <td>2011/12/12</td>
      <td>$106,450</td>
    </tr>
    <tr>
      <td>Doris Wilder</td>
      <td>Sales Assistant</td>
      <td>Sidney</td>
      <td>23</td>
      <td>2010/09/20</td>
      <td>$85,600</td>
    </tr>
    <tr>
      <td>Angelica Ramos</td>
      <td>Chief Executive Officer (CEO)</td>
      <td>London</td>
      <td>47</td>
      <td>2009/10/09</td>
      <td>$1,200,000</td>
    </tr>
    <tr>
      <td>Gavin Joyce</td>
      <td>Developer</td>
      <td>Edinburgh</td>
      <td>42</td>
      <td>2010/12/22</td>
      <td>$92,575</td>
    </tr>
    <tr>
      <td>Jennifer Chang</td>
      <td>Regional Director</td>
      <td>Singapore</td>
      <td>28</td>
      <td>2010/11/14</td>
      <td>$357,650</td>
    </tr>
    <tr>
      <td>Brenden Wagner</td>
      <td>Software Engineer</td>
      <td>San Francisco</td>
      <td>28</td>
      <td>2011/06/07</td>
      <td>$206,850</td>
    </tr>
    <tr>
      <td>Fiona Green</td>
      <td>Chief Operating Officer (COO)</td>
      <td>San Francisco</td>
      <td>48</td>
      <td>2010/03/11</td>
      <td>$850,000</td>
    </tr>
    <tr>
      <td>Shou Itou</td>
      <td>Regional Marketing</td>
      <td>Tokyo</td>
      <td>20</td>
      <td>2011/08/14</td>
      <td>$163,000</td>
    </tr>
    <tr>
      <td>Michelle House</td>
      <td>Integration Specialist</td>
      <td>Sidney</td>
      <td>37</td>
      <td>2011/06/02</td>
      <td>$95,400</td>
    </tr>
    <tr>
      <td>Suki Burks</td>
      <td>Developer</td>
      <td>London</td>
      <td>53</td>
      <td>2009/10/22</td>
      <td>$114,500</td>
    </tr>
    <tr>
      <td>Prescott Bartlett</td>
      <td>Technical Author</td>
      <td>London</td>
      <td>27</td>
      <td>2011/05/07</td>
      <td>$145,000</td>
    </tr>
    <tr>
      <td>Gavin Cortez</td>
      <td>Team Leader</td>
      <td>San Francisco</td>
      <td>22</td>
      <td>2008/10/26</td>
      <td>$235,500</td>
    </tr>
    <tr>
      <td>Martena Mccray</td>
      <td>Post-Sales support</td>
      <td>Edinburgh</td>
      <td>46</td>
      <td>2011/03/09</td>
      <td>$324,050</td>
    </tr>
    <tr>
      <td>Unity Butler</td>
      <td>Marketing Designer</td>
      <td>San Francisco</td>
      <td>47</td>
      <td>2009/12/09</td>
      <td>$85,675</td>
    </tr>
    <tr>
      <td>Howard Hatfield</td>
      <td>Office Manager</td>
      <td>San Francisco</td>
      <td>51</td>
      <td>2008/12/16</td>
      <td>$164,500</td>
    </tr>
    <tr>
      <td>Hope Fuentes</td>
      <td>Secretary</td>
      <td>San Francisco</td>
      <td>41</td>
      <td>2010/02/12</td>
      <td>$109,850</td>
    </tr>
    <tr>
      <td>Vivian Harrell</td>
      <td>Financial Controller</td>
      <td>San Francisco</td>
      <td>62</td>
      <td>2009/02/14</td>
      <td>$452,500</td>
    </tr>
    <tr>
      <td>Timothy Mooney</td>
      <td>Office Manager</td>
      <td>London</td>
      <td>37</td>
      <td>2008/12/11</td>
      <td>$136,200</td>
    </tr>
    <tr>
      <td>Jackson Bradshaw</td>
      <td>Director</td>
      <td>New York</td>
      <td>65</td>
      <td>2008/09/26</td>
      <td>$645,750</td>
    </tr>
    <tr>
      <td>Olivia Liang</td>
      <td>Support Engineer</td>
      <td>Singapore</td>
      <td>64</td>
      <td>2011/02/03</td>
      <td>$234,500</td>
    </tr>
    <tr>
      <td>Bruno Nash</td>
      <td>Software Engineer</td>
      <td>London</td>
      <td>38</td>
      <td>2011/05/03</td>
      <td>$163,500</td>
    </tr>
    <tr>
      <td>Sakura Yamamoto</td>
      <td>Support Engineer</td>
      <td>Tokyo</td>
      <td>37</td>
      <td>2009/08/19</td>
      <td>$139,575</td>
    </tr>
    <tr>
      <td>Thor Walton</td>
      <td>Developer</td>
      <td>New York</td>
      <td>61</td>
      <td>2013/08/11</td>
      <td>$98,540</td>
    </tr>
    <tr>
      <td>Finn Camacho</td>
      <td>Support Engineer</td>
      <td>San Francisco</td>
      <td>47</td>
      <td>2009/07/07</td>
      <td>$87,500</td>
    </tr>
    <tr>
      <td>Serge Baldwin</td>
      <td>Data Coordinator</td>
      <td>Singapore</td>
      <td>64</td>
      <td>2012/04/09</td>
      <td>$138,575</td>
    </tr>
    <tr>
      <td>Zenaida Frank</td>
      <td>Software Engineer</td>
      <td>New York</td>
      <td>63</td>
      <td>2010/01/04</td>
      <td>$125,250</td>
    </tr>
    <tr>
      <td>Zorita Serrano</td>
      <td>Software Engineer</td>
      <td>San Francisco</td>
      <td>56</td>
      <td>2012/06/01</td>
      <td>$115,000</td>
    </tr>
    <tr>
      <td>Jennifer Acosta</td>
      <td>Junior Javascript Developer</td>
      <td>Edinburgh</td>
      <td>43</td>
      <td>2013/02/01</td>
      <td>$75,650</td>
    </tr>
    <tr>
      <td>Cara Stevens</td>
      <td>Sales Assistant</td>
      <td>New York</td>
      <td>46</td>
      <td>2011/12/06</td>
      <td>$145,600</td>
    </tr>
    <tr>
      <td>Hermione Butler</td>
      <td>Regional Director</td>
      <td>London</td>
      <td>47</td>
      <td>2011/03/21</td>
      <td>$356,250</td>
    </tr>
    <tr>
      <td>Lael Greer</td>
      <td>Systems Administrator</td>
      <td>London</td>
      <td>21</td>
      <td>2009/02/27</td>
      <td>$103,500</td>
    </tr>
    <tr>
      <td>Jonas Alexander</td>
      <td>Developer</td>
      <td>San Francisco</td>
      <td>30</td>
      <td>2010/07/14</td>
      <td>$86,500</td>
    </tr>
    <tr>
      <td>Shad Decker</td>
      <td>Regional Director</td>
      <td>Edinburgh</td>
      <td>51</td>
      <td>2008/11/13</td>
      <td>$183,000</td>
    </tr>
    <tr>
      <td>Michael Bruce</td>
      <td>Javascript Developer</td>
      <td>Singapore</td>
      <td>29</td>
      <td>2011/06/27</td>
      <td>$183,000</td>
    </tr>
    <tr>
      <td>Donna Snider</td>
      <td>Customer Support</td>
      <td>New York</td>
      <td>27</td>
      <td>2011/01/25</td>
      <td>$112,000</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>

Now when i use ajax request in the same code the group is *undefined*. **And the other part of the group code doesn't work.** A little research and i found that it might have happened because of ajax request not completely rendered in the table and the endRender might not have known about the group.

So my question is how can i implement the endRender code after ajax request is completely rendered in the datatable so that endRender can know about the rowGroup. Or is there any way to achieve the solution to my problem?

**UPDATED:**

<!-- begin snippet: js hide: false console: false babel: false -->

也更新了 ajax 请求代码

$(document).ready(function() {
    $('#example').DataTable( {
        ajax: 'https://api.myjson.com/bins/zzaca',
        order: [[2, 'asc']],        
        columns: [           
            { data: 'name' },
            { data: 'position' },
            { data: 'office' },
            { data: 'extn' },
            { data: 'start_date' },
            { data: 'salary' }
        ],
        rowsGroup:[2],
        rowGroup: {
            startRender: null,
            endRender: function ( rows, group ) {
                    
                var salaryAvg = rows
                    .data()
                    .pluck(5)
                    .reduce( function (a, b) {
                        return a + b;
                    }, 0) / rows.count();
                salaryAvg = $.fn.dataTable.render.number(',', '.', 0, '$').display( salaryAvg );
 
                var ageAvg = rows
                    .data()
                    .pluck(3)
                    .reduce( function (a, b) {
                        return a + b*1;
                    }, 0) / rows.count();
            console.log(salaryAvg);
            console.log(ageAvg);
                return $('<tr/>')
                    .append( '<td colspan="3">Averages for '+group+'</td>' )
                    .append( '<td>'+ageAvg.toFixed(0)+'</td>' )
                    .append( '<td/>' )
                    .append( '<td>'+salaryAvg+'</td>' );
            },
            dataSrc: 2
        }
    } );
} );

<html>

<head>
    <script src="https://code.jquery.com/jquery-3.3.1.js"></script>
    <script src="https://cdn.datatables.net/1.10.19/js/jquery.dataTables.min.js"></script>
    <script src="https://cdn.datatables.net/rowgroup/1.0.4/js/dataTables.rowGroup.min.js"></script>
    <link rel="stylesheet" href="https://cdn.datatables.net/1.10.19/css/jquery.dataTables.min.css" />
    <link rel="stylesheet" href="https://cdn.datatables.net/rowgroup/1.0.4/css/rowGroup.dataTables.min.css" />
    <script src="https://cdn.rawgit.com/ashl1/datatables-rowsgroup/v1.0.0/dataTables.rowsGroup.js"></script>
    <script src="abcd.js"></script>
</head>

<body>
    <table id="example" class="display" style="width:100%">
        <thead>
            <tr>
               
                <th>Name</th>
                <th>Position</th>
                <th>Office</th>
                <th>Extn.</th>
                <th>Start date</th>
                <th>Salary</th>
            </tr>
        </thead>
        <tfoot>
            <tr>
            
                <th>Name</th>
                <th>Position</th>
                <th>Office</th>
                <th>Extn.</th>
                <th>Start date</th>
                <th>Salary</th>
            </tr>
        </tfoot>
    </table>
</body>

</html>

【问题讨论】：

你的小提琴是空白的
请再检查一遍
好的。因此，您已将行与 Office 分组，并获得了 Office 组中所有薪水的平均值。小组似乎工作正常.. 有什么问题？？
请重新阅读我的问题，同样的代码不适用于 ajax 请求。
你能添加代码吗.. 你是如何在 Datatable 中进行 ajax 调用的... 就像 Question 和 Fiddle ... 两者都有静态数据 ....

标签： datatable datatables

【解决方案1】：

当您处理 ajax 而不是 Array 时，变化很少。

dataSrc: 'office',

datasrc 必须是您要分组的 attr。这里office

var salaryAvg = rows
    .data()
    .reduce( function (a, b) {
        return a + b.salary.replace(/[^\d]/g, '')*1;
    }, 0) / rows.count();

这不是一个数组，所以 pluck() 将不起作用，您需要像这样从 JSON 中获取 attr b.office

var ageAvg = rows
    .data()
    .reduce( function (a, b) {
        return a + b.extn*1;
    }, 0) / rows.count();

extn attr 也一样

完整的 Javascript

$(document).ready(function() {

    $('#example').DataTable( {

    ajax: 'https://api.myjson.com/bins/zzaca',
    order: [[2, 'asc']],        
    columns: [           
        { data: 'name' },
        { data: 'position' },
        { data: 'office' },
        { data: 'extn' },
        { data: 'start_date' },
        { data: 'salary' }
    ],
    rowsGroup:[2],
    rowGroup: {
        dataSrc: 'office',
        startRender: null,
        endRender: function ( rows, group ) {
            var salaryAvg = rows
                .data()
                .reduce( function (a, b) {
                    return a + b.salary.replace(/[^\d]/g, '')*1;
                }, 0) / rows.count();

            salaryAvg = $.fn.dataTable.render.number(',', '.', 0, '$').display( salaryAvg );


            var ageAvg = rows
                .data()
                .reduce( function (a, b) {
                    return a + b.extn*1;
                }, 0) / rows.count();

            return $('<tr/>')
                .append( '<td colspan="3">Averages for '+group+'</td>' )
                .append( '<td>'+ageAvg.toFixed(0)+'</td>' )
                .append( '<td/>' )
                .append( '<td>'+salaryAvg+'</td>' );
        },

    }
    } );
} );

Working Fiddle

编辑 1：

回答：为什么带有 attr 的 datasrc 可以工作，但不能用于其他情况？

在第一种情况下，数据是这样的数组形式

var a = [2, "hello", "test", "$22500"]

您将使用它的索引获得价值

在 ajax 的情况下，您的 Object 类型是 JSON 之类的

var a = {  "name" : "test", "value" : "$22055"}

现在您无法按索引阅读此内容。您可以像这样使用 attr 访问它

a.name // test

【讨论】：

您想解释一下为什么带有 attr 的 datasrc 可以工作，但不能用于其他情况吗？如果你解释一下，我会赞成。