还有另一个关于这个的帖子,我试过了。但有一个问题:如果你删除内容,文本区域不会缩小。我找不到任何方法将其缩小到正确的大小- clientHeight值返回为文本区域的完整大小,而不是它的内容。

该页面的代码如下:

function FitToContent(id, maxHeight)
{
   var text = id && id.style ? id : document.getElementById(id);
   if ( !text )
      return;

   var adjustedHeight = text.clientHeight;
   if ( !maxHeight || maxHeight > adjustedHeight )
   {
      adjustedHeight = Math.max(text.scrollHeight, adjustedHeight);
      if ( maxHeight )
         adjustedHeight = Math.min(maxHeight, adjustedHeight);
      if ( adjustedHeight > text.clientHeight )
         text.style.height = adjustedHeight + "px";
   }
}

window.onload = function() {
    document.getElementById("ta").onkeyup = function() {
      FitToContent( this, 500 )
    };
}

当前回答

对于那些想要在宽度和高度上自动调整文本区域的人:

HTML:

<textarea class='textbox'></textarea>
<div>
  <span class='tmp_textbox'></span>
</div>

CSS:

.textbox,
.tmp_textbox {
  font-family: 'Arial';
  font-size: 12px;
  resize: none;
  overflow:hidden;
}

.tmp_textbox {
  display: none;
}

jQuery:

$(function(){
  //alert($('.textbox').css('padding'))
  $('.textbox').on('keyup change', checkSize)
  $('.textbox').trigger('keyup')

  function checkSize(){
    var str = $(this).val().replace(/\r?\n/g, '<br/>');
    $('.tmp_textbox').html( str )
    console.log($(this).val())

    var strArr = str.split('<br/>')
    var row = strArr.length
    $('.textbox').attr('rows', row)
    $('.textbox').width( $('.tmp_textbox').width() + parseInt($('.textbox').css('padding')) * 2 + 10 )
  }
})

Codepen:

http://codepen.io/anon/pen/yNpvJJ

欢呼,

其他回答

我知道用jquery实现这个的一个简短而正确的方法。没有额外的隐藏div需要和工作在大多数浏览器

<script type="text/javascript">$(function(){
$("textarea").live("keyup keydown",function(){
var h=$(this);
h.height(60).height(h[0].scrollHeight);//where 60 is minimum height of textarea
});});

</script>
$('textarea').bind('keyup change', function() {
    var $this = $(this), $offset = this.offsetHeight;
    $offset > $this.height() && $offset < 300 ?
        $this.css('height ', $offset)
            .attr('rows', $this.val().split('\n').length)
            .css({'height' : $this.attr('scrollHeight'),'overflow' : 'hidden'}) :
        $this.css('overflow','auto');
});

自动调整大小

https://github.com/jackmoore/autosize

只是作品,独立,很受欢迎(截至2018年10月,3.0k+ GitHub星),可在cdnjs上使用)和轻量级(~3.5k)。演示:

<textarea id=“autosize” style=“width:200px;”>a 我一 C</textarea> <script src=“https://cdnjs.cloudflare.com/ajax/libs/autosize.js/4.0.2/autosize.min.js”></script> <script>autosize(document.querySelectorAll('#autosize'));</script>

顺便说一句,如果你正在使用ACE编辑器,请使用maxLines: Infinity:自动调整ACE Cloud 9编辑器中的内容高度

有人觉得满意吗?没有混乱的滚动,和唯一的JS我喜欢关于它是如果你计划在模糊保存数据…显然,它在所有流行的浏览器上都是兼容的:http://caniuse.com/#feat=contenteditable

只要把它设置成文本框的样式,它就会自动调整大小……将它的最小高度设置为首选文本高度。

这种方法的最酷之处在于,您可以在某些浏览器上保存和标记。

http://jsfiddle.net/gbutiri/v31o8xfo/

var _auto_value = ''; $(document).on('blur', '.autosave', function(e) { var $this = $(this); if ($this.text().trim() == '') { $this.html(''); } // The text is here. Do whatever you want with it. $this.addClass('saving'); if (_auto_value !== $this.html() || $this.hasClass('error')) { // below code is for example only. $.ajax({ url: '/echo/json/?action=xyz_abc', data: 'data=' + $this.html(), type: 'post', datatype: 'json', success: function(d) { console.log(d); $this.removeClass('saving error').addClass('saved'); var k = setTimeout(function() { $this.removeClass('saved error') }, 500); }, error: function() { $this.removeClass('saving').addClass('error'); } }); } else { $this.removeClass('saving'); } }).on('focus mouseup', '.autosave', function() { var $this = $(this); if ($this.text().trim() == '') { $this.html(''); } _auto_value = $this.html(); }).on('keyup', '.autosave', function(e) { var $this = $(this); if ($this.text().trim() == '') { $this.html(''); } }); body { background: #3A3E3F; font-family: Arial; } label { font-size: 11px; color: #ddd; } .autoheight { min-height: 16px; font-size: 16px; margin: 0; padding: 10px; font-family: Arial; line-height: 20px; box-sizing: border-box; -o-box-sizing: border-box; -moz-box-sizing: border-box; -webkit-box-sizing: border-box; overflow: hidden; display: block; resize: none; border: 0; outline: none; min-width: 200px; background: #ddd; max-height: 400px; overflow: auto; } .autoheight:hover { background: #eee; } .autoheight:focus { background: #fff; } .autosave { -webkit-transition: all .2s; -moz-transition: all .2s; transition: all .2s; position: relative; float: none; } .autoheight * { margin: 0; padding: 0; } .autosave.saving { background: #ff9; } .autosave.saved { background: #9f9; } .autosave.error { background: #f99; } .autosave:hover { background: #eee; } .autosave:focus { background: #fff; } [contenteditable=true]:empty:before { content: attr(placeholder); color: #999; position: relative; top: 0px; /* For IE only, do this: position: absolute; top: 10px; */ cursor: text; } <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <label>Your Name</label> <div class="autoheight autosave contenteditable" contenteditable="true" placeholder="Your Name"></div>

React的一个示例实现:

const { useLayoutEffect, useState, useRef } = React; const TextArea = () => { const ref = useRef(); const [value, setValue] = useState('Some initial text that both wraps and uses\nnew\nlines'); // This only tracks the auto-sized height so we can tell if the user has manually resized const autoHeight = useRef(); useLayoutEffect(() => { if (!ref.current) { return; } if ( autoHeight.current !== undefined && ref.current.style.height !== autoHeight.current ) { // don't auto size if the user has manually changed the height return; } ref.current.style.height = "auto"; ref.current.style.overflow = "hidden"; const next = `${ref.current.scrollHeight}px`; ref.current.style.height = next; autoHeight.current = next; ref.current.style.overflow = "auto"; }, [value, ref, autoHeight]); return ( <textarea ref={ref} style={{ resize: 'vertical', minHeight: '1em', }} value={value} onChange={event => setValue(event.target.value)} /> ); } ReactDOM.render(<TextArea />, document.getElementById('app')) <script src="https://cdnjs.cloudflare.com/ajax/libs/react/17.0.1/umd/react.production.min.js"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/17.0.1/umd/react-dom.production.min.js"></script> <div id="app"></div>