Dynamically Generate Text Areas W/ Unique Id's Based On Checkbox Inputs

April 29, 2023 Post a Comment

I am working on a program for my company to process different product types and create files. I have a form that will eventually grow to close to 150 checkbox options over the cour

Solution 1:

You may try this

HTML

<form action="some_action.php" method="post">
    <input type="checkbox" value="NOT" name="size">NOT<br />
    <input type="checkbox" value="THA" name="size">THA<br />
    <input type="checkbox" value="TAB22" name="size">TAB22<br />
    .... 
</form>

$('input:checkbox[name="size"]').on('click', function(){
    if($(this).is(':checked'))
    {
        $('<div class="inputArea"></div>') // inputArea is a class not an ID because ID should be anique
        .append($('<textarea />', {id:'txtArea_'+$(this).val(), name:'txtArea_'+$(this).val()}))
        .insertAfter($(this).next('br'));
    }
    else
    {
        $(this).next('br').next('div.inputArea').remove();
    }
});

DEMO.

Every textarea has name and id with prefix txtArea_ with value of it's corresponding checkbox so if a checkbox is submitted and it's value is NOT then you can retrive the value of that corresponding textarea in php as

$txtArea_NOT=$_POST['txtArea_NOT']; // When form's method is post

Solution 2:

If you're using jQuery, you should be able to use/modify the following as a base.

$('input[type=checkbox]').click(function() {
  var value = $(this).val();
  $(this).append(value +'<br /><textarea name="'+ value +'"></textarea>');
});

Solution 3:

You can try to use the Wrap and unwrap methods to get your things done.

Remember ID's should be unique in a page. So instead of id I have assigned it a class for the textarea div..

$('input[type=checkbox]').on('click', function() {
    var isChecked = $(this).is(':checked');
    if (isChecked) {
        $(this).wrap('<div class="inputArea"></div>');
        $(this).closest('div').prepend('<textarea class="text-area" cols="10" rows="2"></textarea>');
    }
    else{
       $(this).closest('div').find('.text-area').remove();
        $(this).unwrap();
    }
});

DEMO HERE

So basically your are wrapping your checkbox inside a div and assigning it.. When you uncheck it , the wrapper is removed... This is independent of other checkboxe's. So it should work for any number of checkboxes.

Solution 4:

HTML

You should have unique ids for the checkboxes, just as good practice. This also will show/hide textareas, to preserve any text that has already been entered -- this could be a good or a bad thing, depending on your requirements.

<form name="frmSize" method="POST" action="somePage.php">
    <div><input id="cbNot" class="cbFileList" type="checkbox" value="NOT" name="not">NOT</div>
    <div><input id="cbTha" class="cbFileList" type="checkbox" value="THA" name="tha">THA</div>
    <div><input id="cbTab22" class="cbFileList" type="checkbox" value="TAB22" name="tab22">TAB22</div>
</form>

JavaScript

var cbList = document.getElementsByClassName( 'cbFileList' );
var i;

for ( i = 0; i < cbList.length; i++ ) {
    createTextArea( cbList[i] );
    cbList[i].addEventListener( 'click', function() {
        var cb = this;
        if ( cb.checked ) {
            showTextArea( cb );
        } else {
            hideTextArea( cb );
        }
    });
}

function showTextArea( cb ) {
    document.getElementById( 'div-' + cb.id).style.display = '';
}

function hideTextArea( cb ) {
    document.getElementById( 'div-' + cb.id).style.display = 'none';
}

function createTextArea( cb ) {
    var newDiv = document.createElement( 'div' );
    var newTextArea = document.createElement( 'textarea' );

    newDiv.setAttribute( 'id', 'div-' + cb.id );
    newDiv.innerHTML = '<b>' + cb.value + '</b><br/>'; // Create bold text using checkbox's value

    newTextArea.setAttribute( 'id', 'ta-' + cb.id );
    newTextArea.setAttribute( 'name', 'ta-' + cb.id );
    newTextArea.innerHTML = cb.value;

    newDiv.appendChild( newTextArea );
    cb.parentNode.appendChild( newDiv );
}

The Output

<div>
    <input id="cbNot" class="cbFileList" type="checkbox" value="NOT" name="not">NOT
    <div id="div-cbNot">
        <b>NOT</b><br/>
        <textarea id="ta-cbNot"></textarea>
    </div>
</div>
<div>
    <input id="cbTha" class="cbFileList" type="checkbox" value="THA" name="tha">THA
    <div id="div-cbTha">
        <b>THA</b><br/>
        <textarea id="ta-cbTha" name="ta-cbTha"></textarea>
    </div>
</div>
...

PHP

<?
    // run a for loop through $_POST[] and check for any field prefixed with 'ta-'
    foreach( $_POST as $key => $value ) {
        if ( strpos( $key, 'ta-' ) !== false && strlen( $value ) > 0 ) {
            // Found a textarea with content!
            // Do something with $_POST[$key], which contains the contents of textarea
        }
    }
?>

JavaScript Free