[javascript] jQuery: selecting each td in a tr

I need a way to interact with each td element in a tr.

To elaborate, I would like to access the first table row, then the first column, then the second column, etc. Then move onto the second row and repeat the process.

Something like this (pseudo-code):

for each row in table
{
  for each column in row
  {
    do cool things
  }
}

jQuery:

$('#tblNewAttendees tr').each(function() {
  alert('tr');
  //Cool jquery magic that lets me iterate over all the td only in this row
  $(magicSelector).each(function(){
    alert('hi');
  });

});

HTML:

<table>
     <thead>
          <th>someHeader</th>
     </thead>
     <tbody>
          <tr>
               <td>want to grab this first</td>
               <td> this second </td>
          </tr>
          <tr>
               <td>this third</td>
               <td>this fourth</td>
          </tr>
     </tbody>
</table>

You don't need a jQuery selector at all. You already have a reference to the cells in each row via the cells property.

$('#tblNewAttendees tr').each(function() {

    $.each(this.cells, function(){
        alert('hi');
    });

});

It is far more efficient to utilize a collection that you already have, than to create a new collection via DOM selection.

Here I've used the jQuery.each()^(docs) method which is just a generic method for iteration and enumeration.

Fully example to demonstrate how jQuery query all data in HTML table.

Assume there is a table like the following in your HTML code.

<table id="someTable">
  <thead>
    <tr>
      <td>title 0</td>
      <td>title 1</td>
      <td>title 2</td>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td>row 0 td 0</td>
      <td>row 0 td 1</td>
      <td>row 0 td 2</td>
    </tr>
    <tr>
      <td>row 1 td 0</td>
      <td>row 1 td 1</td>
      <td>row 1 td 2</td>
    </tr>
    <tr>
      <td>row 2 td 0</td>
      <td>row 2 td 1</td>
      <td>row 2 td 2</td>
    </tr>
    <tr> ... </tr>
    <tr> ... </tr>
    ...
    <tr> ... </tr>
    <tr>
      <td>row n td 0</td>
      <td>row n td 1</td>
      <td>row n td 2</td>
    </tr>
  </tbody>
</table>

Then, The Answer, the code to print all row all column, should like this

$('#someTable tbody tr').each( (tr_idx,tr) => {
    $(tr).children('td').each( (td_idx, td) => {
        console.log( '[' +tr_idx+ ',' +td_idx+ '] => ' + $(td).text());
    });                 
});

After running the code, the result will show

[0,0] => row 0 td 0
[0,1] => row 0 td 1
[0,2] => row 0 td 2
[1,0] => row 1 td 0
[1,1] => row 1 td 1
[1,2] => row 1 td 2
[2,0] => row 2 td 0
[2,1] => row 2 td 1
[2,2] => row 2 td 2
...
[n,0] => row n td 0
[n,1] => row n td 1
[n,2] => row n td 2

Summary.
In the code,
tr_idx is the row index start from 0.
td_idx is the column index start from 0.

From this double-loop code,
you can get all loop-index and data in each td cell after comparing the Answer's source code and the output result.

Your $(magicSelector) could be $('td', this). This will grab all td that are children of this, which in your case is each tr. This is the same as doing $(this).find('td').

$('td', this).each(function() {
// Logic
});

expanding on the answer above the 'each' function will return you the table-cell html object. wrapping that in $() will then allow you to perform jquery actions on it.

$(this).find('td').each (function( column, td) {
  $(td).blah
});  

$('#tblNewAttendees tbody tr).each((index, tr)=> {
        //console.log(tr);
        $(tr).children('td').each ((index, td) => {
            console.log(td);

        }); 

    });

You can use this tr and td parameter also.