Extract excel error: undefined (reading 'length') from footer

imneckro

WHen I'm trying to extra excel, footer throws error:

buttons.html5.min.js:8 Uncaught TypeError: Cannot read properties of undefined (reading 'length')
at buttons.html5.min.js:8:21584
at _Api.action (buttons.html5.min.js:8:21857)
at run (dataTables.buttons.js:807:19)
at dataTables.buttons.js:822:7

If remove footer excel exports fine.
Here is my code:

                  $('#getvatinfo').dataTable({
                      dataSrc: '',
                      bPaginate: false,
                      "info": false,
                      "paging": false,
                      layout: {
                          topStart: {
                              buttons: ['copy', 'csv', 'excel', 'pdf', 'print']
                          }
                      },
                      columnDefs: [{
                              target: 1,
                              render: function(data) {
                                  return moment(data).format('DD/MM/YYYY');
                              }
                          },
                          {
                              targets: [5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42],
                              render: DataTable.render.number(null, null, 2, '')
                          }
                      ],
                      "language": {
                          "search": "Αναζήτηση"
                      },
                      "footerCallback": function(row, data, start, end, display) {
                          var api = this.api(),
                              data;

                          // Remove the formatting to get integer data for summation
                          var intVal = function(i) {
                              return typeof i === 'string' ?
                                  i.replace(/[\$a-zA-Z, ]/g, '') * 1 :
                                  typeof i === 'number' ?
                                  i : 0;
                          };

                          var cols = [5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42]; // your columns position will come in this array

                          for (let index = 0; index < cols.length; index++) {
                              var col_data = cols[index];
                              // Total over all pages
                              total = api
                                  .column(col_data)
                                  .data()
                                  .reduce(function(a, b) {
                                      return intVal(a) + intVal(b);
                                  }, 0);

                              // Total over this page
                              pageTotal = api
                                  .column(col_data, {
                                      page: 'current'
                                  })
                                  .data()
                                  .reduce(function(a, b) {
                                      return intVal(a) + intVal(b);
                                  }, 0);

                              // Update footer
                              $(api.column(col_data).footer()).html(
                                  pageTotal.toLocaleString('el-GR', {
                                      minimumFractionDigits: 2
                                  })
                              );
                          }

                      },
                      initComplete: function(settings, json) {
                          $("#perfrom").text(datefrom);
                          $("#perto").text(dateto);
                          fillper();
                      }
                  });

kthorngren

Exporting seems to work fine with two footer rows in this test case:
https://live.datatables.net/qexunane/1/edit

Possibly the problem is with the structure of your footer. Please provide a link to your page or test case replicating the issue so we can help debug.
https://datatables.net/manual/tech-notes/10#How-to-provide-a-test-case

Kevin

imneckro

Here is my table:

https://justpaste.it/ewfn2

kthorngren

I copied your table into this updated test case and it still works.
https://live.datatables.net/yequpene/1/edit

Please provide a link to your page or build a test case that replaictes the issue so we can help debug.
https://datatables.net/manual/tech-notes/10#How-to-provide-a-test-case

Kevin

kthorngren

Looks like the issue might be with using the footerCallback to update the footer. I used this example and it throws the following error when exporting Excel:

datatables.min.js:60 Uncaught TypeError: Cannot read properties of undefined (reading 'length')

Here is the test case:
https://live.datatables.net/qanageto/1/edit

@allan will need to take a look.

Kevin

kthorngren

I just remembered the issue in this thread. You are running into the same issue which has a fix. The next release of buttons.html5.js will have the fix. Or you can download the buttons.html5.js nightly from here which has the fix then pickup the next version once released.

Here is the updated test case with buttons.html5.js nightly and it exports with no errors:
https://live.datatables.net/sulehuso/1/edit

Kevin

imneckro

Kevin thanks a lot for your help.
With nightly version error no longer occurs.
Exported excel footer sums though are empty.

kthorngren

I noticed that too. I started this thread. There is a fix in the nightly code or you can wait until the official release of the next versions. Maybe next week.

Kevin

imneckro

I'm using https://nightly.datatables.net/buttons/js/buttons.html5.js but still footer empty.

kthorngren

Allan stated this:

I think it would be correct for Buttons and DataTables to handle this situation, so I've made a couple of commits (1, 2) to address it.

The fix was placed in two places. So you will probably also need the nightly datatables.js.

Kevin