Auto expand a textarea using jQuery

Question

How can I make a textarea automatically expand using jQuery?

I have a textbox for explaining the agenda of the meeting, so I want to expand that textbox when my agenda's text keep growing that textbox area.

Answer 1

This worked for me better:

$('.resiText').on('keyup input', function() { 
$(this).css('height', 'auto').css('height', this.scrollHeight + (this.offsetHeight - this.clientHeight));
});

.resiText {
    box-sizing: border-box;
    resize: none;
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<textarea class="resiText"></textarea>

Answer 2

Grows / Shrinks textarea. This demo utilizes jQuery for event binding, but it's not a must in any way.
(no IE support - IE doesn't respond to rows attribute change)

DEMO PAGE

---

HTML

<textarea class='autoExpand' rows='3' data-min-rows='3' placeholder='Auto-Expanding Textarea'></textarea>

CSS

textarea{  
  display:block;
  box-sizing: padding-box;
  overflow:hidden;

  padding:10px;
  width:250px;
  font-size:14px;
  margin:50px auto;
  border-radius:8px;
  border:6px solid #556677;
}

javascript (updated)

$(document)
    .one('focus.textarea', '.autoExpand', function(){
        var savedValue = this.value;
        this.value = '';
        this.baseScrollHeight = this.scrollHeight;
        this.value = savedValue;
    })
    .on('input.textarea', '.autoExpand', function(){
        var minRows = this.getAttribute('data-min-rows')|0,
            rows;
        this.rows = minRows;
        rows = Math.ceil((this.scrollHeight - this.baseScrollHeight) / 16);
        this.rows = minRows + rows;
    });

Answer 3

I've used the Textarea Expander jQuery plugin before with good results.

Answer 4

To define a auto expandable textarea, you have to do two things:

1. Expand it once you click Enter key inside it, or type content more than one line.
2. And shrink it at blur to get the actual size if user has entered white spaces.(bonus)

Here is a handmade function to accomplish the task.

Working fine with almost all browser ( < IE7 ). Here is the method:

    //Here is an event to get TextArea expand when you press Enter Key in it.
    // intiate a keypress event
    $('textarea').keypress(function (e) {  
       if(e.which == 13)   {   
       var control = e.target;                     
       var controlHeight = $(control).height();          
      //add some height to existing height of control, I chose 17 as my line-height was 17 for the control    
    $(control).height(controlHeight+17);  
    }
    }); 

$('textarea').blur(function (e) {         
    var textLines = $(this).val().trim().split(/\r*\n/).length;      
    $(this).val($(this).val().trim()).height(textLines*17);
    });

HERE is a post about this.

Answer 5

I wanted animations and auto-shrink. The combination is apparently hard, because people came up with pretty intense solutions for it. I've made it multi-textarea-proof, too. And it isn't as ridiculously heavy as the jQuery plugin.

I've based myself on vsync's answer (and the improvement he made for it), http://codepen.io/anon/pen/vlIwj is the codepen for my improvement.

HTML

<textarea class='autoExpand' rows='3' data-min-rows='3' placeholder='Auto-Expanding Textarea'></textarea>

CSS

body{ background:#728EB2; }

textarea{  
  display:block;
  box-sizing: padding-box;
  overflow:hidden;

  padding:10px;
  width:250px;
  font-size:14px;
  margin:50px auto;
  border-radius:8px;
  border:6px solid #556677;
  transition:all 1s;
  -webkit-transition:all 1s;
}

JS

var rowheight = 0;

$(document).on('input.textarea', '.autoExpand', function(){
    var minRows = this.getAttribute('data-min-rows')|0,
        rows    = this.value.split("\n").length;
    $this = $(this);
    var rowz = rows < minRows ? minRows : rows;
    var rowheight = $this.attr('data-rowheight');
    if(!rowheight){
      this.rows = rowz;
      $this.attr('data-rowheight', (this.clientHeight  - parseInt($this.css('padding-top')) - parseInt($this.css('padding-bottom')))/ rowz);
    }else{
      rowz++;
      this.style.cssText = 'height:' + rowz * rowheight + 'px'; 
    }
});

Answer 6

• Auto Growing Textareas
• jQuery Autosize