Dynamically expand height of input type “text” based on number of characters typed into field

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遇见更好的自我 2020-12-01 10:26
Similar to the below JSFiddle (which I bookmarked and do not know from where the original question emerged):
http://jsfiddle.net/mJMpw/6/

      
      
        
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                   北荒
                                             
                
                
                (楼主)
            
              
              
                2020-12-01 10:44
              

            
            
                        
UPDATED[2]:

As scrollHeight is always equal to height, we have to set height to '1' before scrollHeight, then when we delete characters the </code> autofit:</p>

<pre><code>$('textarea').on('keydown', function(e){
    if(e.which == 13) {e.preventDefault();}
}).on('input', function(){
    $(this).height(1);
    var totalHeight = $(this).prop('scrollHeight') - parseInt($(this).css('padding-top')) - parseInt($(this).css('padding-bottom'));
    $(this).height(totalHeight);
});
</code></pre>

<p>Fiddle:</p>

<p>http://jsfiddle.net/mJMpw/551/</p>

<p><strong>UPDATED:</strong></p>

<p>As friends said, <code><input type="text"/></code> has no line breaks. My suggest using <code><textarea></code> is:</p>

<pre><code>$('textarea').on({input: function(){
    var totalHeight = $(this).prop('scrollHeight') - parseInt($(this).css('padding-top')) - parseInt($(this).css('padding-bottom'));
    $(this).css({'height':totalHeight});
}
});
</code></pre>

<p>Fiddle:</p>

<p>http://jsfiddle.net/mJMpw/548/</p>

<p><strong>ORIGINAL ANSWER:</strong></p>

<p>this is very ugly but you could do it like this:</p>

<pre><code>$('input[type="text"]').on('keyup',function(){
    var text = $(this).val();
    var getWidth = $('<span class="getWidth" style="white-space:nowrap; width:auto;">' + text + '</span>').insertAfter(this);
    $(this).css({'width':getWidth.outerWidth()}).next('.getWidth').remove();
});
</code></pre>

<p>You have to specify the same fonts/padding property to .getWidth and you input:</p>

<pre><code>input, .getWidth {
    font-family:arial;
    font-size:12px;
    font-weight:normal;
    letter-spacing:normal;
    padding:3px;
}
</code></pre>

<p>Fiddle:</p>

<p>http://jsfiddle.net/9SMRf/</p>
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