Uncaught TypeError: Cannot read property 'clas

问题:

The following error is being thrown in Google Chrome's developers tools:

Uncaught TypeError: Cannot read property 'className' of undefined

The code on which the error is being thrown is:

var oTable = $('#resultstable').dataTable({
                            "bAutoWidth" : true,
                            "iDisplayLength" : 10,
                            "bFilter" : false,
                            "bLengthChange" : false
                        });

resultstable is the id of a table in the html:

<table cellpadding="0" cellspacing="0" border="0" id="resultstable"
                    name="resultstable" class="display datatable">

The weird thing is that after the table tag there is an if statement. The table runs perfectly fine and the CSS shows up correctly when the program is sent into the else if{} section, but it throws the above error and no CSS is applied when it is in the if{} section.

Help please!

回答1:

The other answer put me on the right track.

More succinctly, the error was that the table I was creating was incorrect.

My header columns (inside a thead of course), did not match up with my row columns (inside the tbody)

In my situation, I had too many columns inside the header.

回答2:

Another possible cause is if you list more columns in the "aoColumnDefs" attribute than there are "td" elements in the table.

var yourTable = $('#product-search-results-table').dataTable({
    // If you only have three columns in the HTML table, then this line will cause an error, because it lists four columns in "aoColumnDefs".
    "aoColumnDefs": [{ "bSortable": false, "aTargets": [0, 1, 2, 3] }]
});

回答3:

Datatables requires that your html table is perfect. I found that I got this error when I did not have an equal amount of <th> and <td>. Make sure you do not have an extra header.

回答4:

I got an identical error to the one you're getting now. I once encountered a very similar error using the Chosen library. The problem was (in Chosen's case) that IDs with the [] characters were being used, thus confusing Javascript between css selectors and ids (remember that in CSS we can use [] to specify attributes).

In the case of DataTables, however, I noticed that the DataTables script itself was prepending class = " " before the first element in every tr element within the tbody.

The reason for this was because the HTML output from the php had a logical error. The faulting code:

<?php
for ($currentRow = 0 ; $currentRow <= $query_length; $currentRow++) {
        ?>
        <tr>
        <?php
        list($job_id, $company_id, $job_title, $industry_id, $profession_int, $job_openings, $job_city, $job_salary_start, $job_end_date, $job_start_date, $job_skills, $company_name, $isConfidential, $job_experience_level) = dbRow($query_results, $currentRow);
      echo "<td class = \"detailed-job-row\">" . $job_title . "</td>";
      echo "<td class = \"detailed-job-row\">" . $company_name . "</td>";
      echo "<td class = \"detailed-job-row\">" . $industry_id . "</td>";
      echo "<td class = \"detailed-job-row\">" . $profession_int . "</td>";
      echo "<td class = \"detailed-job-row\">" . $job_openings . "</td>";
      echo "<td class = \"detailed-job-row\">" . $job_city . "</td>";
      echo "<td class = \"detailed-job-row\">" . $job_salary_start . "</td>";
      echo "<td class = \"detailed-job-row\">" . $job_end_date . "</td>";
      echo "<td class = \"detailed-job-row\">" . $job_start_date . "</td>";
      echo "<td class = \"detailed-job-row\">" . $job_skills . "</td>";
      echo "<td class = \"detailed-job-row\">" . $job_experience_level . "</td>";
      ?>
        </tr>
        <?php  
     } ?>
    </tbody>
  </table>
<?php
}
?>

There was an error at the bottom of the long, long table, indicating that postgres could not jump to row 208. This told me I needed to stop looping at i - 1, or $currentRow - 1.

Hence the fixed, working code:

<?php
for ($currentRow = 0 ; $currentRow <= $query_length - 1; $currentRow++) {
        ?>
        <tr>
        <?php
        list($job_id, $company_id, $job_title, $industry_id, $profession_int, $job_openings, $job_city, $job_salary_start, $job_end_date, $job_start_date, $job_skills, $company_name, $isConfidential, $job_experience_level) = dbRow($query_results, $currentRow);
      echo "<td class = \"detailed-job-row\">" . $job_title . "</td>";
      echo "<td class = \"detailed-job-row\">" . $company_name . "</td>";
      echo "<td class = \"detailed-job-row\">" . $industry_id . "</td>";
      echo "<td class = \"detailed-job-row\">" . $profession_int . "</td>";
      echo "<td class = \"detailed-job-row\">" . $job_openings . "</td>";
      echo "<td class = \"detailed-job-row\">" . $job_city . "</td>";
      echo "<td class = \"detailed-job-row\">" . $job_salary_start . "</td>";
      echo "<td class = \"detailed-job-row\">" . $job_end_date . "</td>";
      echo "<td class = \"detailed-job-row\">" . $job_start_date . "</td>";
      echo "<td class = \"detailed-job-row\">" . $job_skills . "</td>";
      echo "<td class = \"detailed-job-row\">" . $job_experience_level . "</td>";
      ?>
        </tr>
        <?php  
     } ?>
    </tbody>
  </table>
<?php
}
?>

Performing this change allowed DataTables to perform properly.

So although I cannot provide a working solution, I do advise you to look at your html mark-up, as that may be the source of your problem (ex, does your table have a tbody?).

回答5:

In my specific case, I had the aTargets properties set with array indices outside the bounds for my elements.

$('.datatable').dataTable({
  aoColumnDefs: [
    {
      bSortable: false,
      aTargets: [0, 6]
    }
  ],
  aaSorting: []
});

This set that there were 7 td columns, but there were only 6. Changing it to the following corrected it:

$('.datatable').dataTable({
  aoColumnDefs: [
    {
      bSortable: false,
      aTargets: [0, 5]
    }
  ],
  aaSorting: []
});

回答6:

It's throwing this error because when dom first loads you were using before declare.

for this error i had one solution written below:

you can add if condition particular element is not undefined like below

if(document.getElementsByTagName('button') !== undefined){
  // and write your needed code here
}

回答7:

Encountered similar problem. Root case was that while dataTable was about to take control of the table, our code also tried to manipulate properties of the table a the same time. The error message does not say so, however, once the table was left to be managed solely by dataTable, the problem was gone.