Question

This script stops working the moment I add a table inside a table, so how to get it worked?
I don’t need any jQuery solutions, I want pure JavaScript. Here’s my script found on the Internet:

<script>

  function show_hide_column(col_no, do_show) {

    var stl;
    if (do_show) stl = 'block'
    else         stl = 'none';

    var tbl  = document.getElementById('id_of_table');
    var rows = tbl.getElementsByTagName('tr');

    for (var row=1; row<rows.length;row++) {
      var cels = rows[row].getElementsByTagName('td')
      cels[col_no].style.display=stl;
    }
  }

</script>

Here’s my HTML:

<table id='id_of_table' border=1>
  <tr><td colspan="4"><table><tr><td></td></tr></table></td></tr>
  <tr><td>  2</td><td>   two</td><td>   deux</td><td>     zwei</td></tr>
  <tr><td>  3</td><td> three</td><td>  trois</td><td>     drei</td></tr>
  <tr><td>  4</td><td>  four</td><td>quattre</td><td>     vier</td></tr>
  <tr><td>  5</td><td>  five</td><td>   cinq</td><td>f&uuml;nf</td></tr>
  <tr><td>  6</td><td>   six</td><td>    six</td><td>    sechs</td></tr>
</table>

And here’s my Form:

<form>
  Enter column no: <input type='text' name=col_no><br>
  <input type='button' onClick='javascript:show_hide_column(col_no.value,  true);' value='show'>
  <input type='button' onClick='javascript:show_hide_column(col_no.value, false);' value='hide'>
</form>

Answer 1

You can leverage the col tag and then the solution is straightforward using only vanilla JavaScript. The col tag has only a few CSS attributes, but visibility is one of them:

function show_hide_column( col_no, do_show ){
   const table  = document.getElementById( 'id_of_table' )
   const column = table.getElementsByTagName( 'col' )[col_no]
   if ( column ){
      column.style.visibility = do_show?"":"collapse";
   }
}

const btnHide = document.getElementById( 'btnHide' )
btnHide.addEventListener( "click", () => show_hide_column( 2, false ))

const btnShow = document.getElementById( 'btnShow' )
btnShow.addEventListener( "click", () => show_hide_column( 2, true ))

 <table id='id_of_table' border=1>
      <col class="col1"/>
      <col class="col2"/>
      <col class="col3"/>
      <col class="col4"/>
      <tr><td colspan="4"><table><tr><td></td></tr></table></td></tr>
      <tr><td>  2</td><td>   two</td><td>   deux</td><td>     zwei</td></tr>
      <tr><td>  3</td><td> three</td><td>  trois</td><td>     drei</td></tr>
      <tr><td>  4</td><td>  four</td><td>quattre</td><td>     vier</td></tr>
      <tr><td>  5</td><td>  five</td><td>   cinq</td><td>fÜnf</td></tr>
      <tr><td>  6</td><td>   six</td><td>    six</td><td>    sechs</td></tr>
    </table>
    <button id="btnHide">hide French</button>
    <button id="btnShow">show French</button>

References:

• col
• visibility on quirksmode