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 )
};
}
如果你不需要支持IE8,你可以使用input事件:
var resizingTextareas = [].slice.call(document.querySelectorAll('textarea[autoresize]'));
resizingTextareas.forEach(function(textarea) {
textarea.addEventListener('input', autoresize, false);
});
function autoresize() {
this.style.height = 'auto';
this.style.height = this.scrollHeight+'px';
this.scrollTop = this.scrollHeight;
window.scrollTo(window.scrollLeft,(this.scrollTop+this.scrollHeight));
}
现在你只需要添加一些CSS,你就完成了:
textarea[autoresize] {
display: block;
overflow: hidden;
resize: none;
}
用法:
<textarea autoresize>Type here and I’ll resize.</textarea>
你可以在我的博客文章中阅读更多关于它是如何工作的。
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>