jQuery - textarea 自适应内容高度

 1 <textarea id="textarea"></textarea>
 2 <script>
 3 function makeExpandingArea(el) {
 4     var setStyle = function(el) {
 5         el.style.height = 'auto';
 6         el.style.height = el.scrollHeight + 'px';
 7         // console.log(el.scrollHeight);
 8     }
 9     var delayedResize = function(el) {
10         window.setTimeout(function() {
11             setStyle(el);
12         },
13         0);
14     }
15     if (el.addEventListener) {
16         el.addEventListener('input',function() {
17             setStyle(el);
18         },false);
19         setStyle(el);
20     } else if (el.attachEvent) {
21         el.attachEvent('onpropertychange',function() {
22             setStyle(el);
23         });
24         setStyle(el);
25     }
26     if (window.VBArray && window.addEventListener) { //IE9
27         el.attachEvent("onkeydown",function() {
28             var key = window.event.keyCode;
29             if (key == 8 || key == 46) delayedResize(el);
30         });
31         el.attachEvent("oncut",function() {
32             delayedResize(el);
33         }); //处理粘贴
34     }
35 }
36 makeExpandingArea(textarea);
37 </script>

觉得不好看可以自己进行美化，修改样式就行了