实现复制粘贴文本过滤（保留文字和图片）
demo如下：
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title></title>
<base href=""/>
<style type="text/css">
</style>
</head>
<body>
<div id="conversation-content" contenteditable="true" style="width:500px;height:300px;background:#f00;"> </div>
</body>
</html>
<script src="http://www.w3school.com.cn/jquery/jquery-1.11.1.min.js"></script>
<script type="text/javascript">
function filterHtml(str,callback){
var s = '';
var imgWidth = 200;
var d = str.replace(/( )/ig,'');//先过滤空格
var sd = d.replace(/<br([^<>]+|\s?)>/ig,'||||');//替换br标签
var div = document.createElement('div');
div.id = 'cache_Id';
div.style.display = 'none';
div.innerHTML = sd;
document.body.appendChild(div);
var dssD = document.getElementById('cache_Id');
var text = dssD.innerText;//过滤html标签
text = text.replace(/\|\|\|\|/g,'<br>');//还原br
var imagesCount = 0;
try{
var temp = '';
var img = dssD.getElementsByTagName('img');
if(img.length > 0){
for(var i=0;i<img.length;i++){
var imgObj = new Image();
imgObj.onload = function(){
imagesCount++;
var w = this.width;
var h = this.height;
if(w > imgWidth){
temp += '<img src="'+ this.src +'" width="'+ imgWidth +'" /><br>';
}else{
temp += '<img src="'+ this.src +'" width="'+ w +'" /><br>';
}
if(imagesCount == img.length){
text+=temp;
s = text;
var n = document.getElementById('cache_Id');
if(n && n.parentNode && n.tagName != 'BODY'){
n.parentNode.removeChild(n);
}
if(callback){
callback(s);
}
}
}
imgObj.onerror = onabort = function(){
console.log(imagesCount);
imagesCount++;
if(imagesCount == img.length){
s = text;
var n = document.getElementById('cache_Id');
if(n && n.parentNode && n.tagName != 'BODY'){
n.parentNode.removeChild(n);
}
if(callback){
callback(s);
}
}
}
imgObj.src = img[i].src;
}
}else{
s = text;
var n = document.getElementById('cache_Id');
if(n && n.parentNode && n.tagName != 'BODY'){
n.parentNode.removeChild(n);
}
if(callback){
callback(s);
}
}
}catch(e){
console.log(e);
}
}
$('#conversation-content')[0].onpaste = function(){
console.log(1);
setTimeout(function(){
filterHtml($('#conversation-content').html(),function(str){
$('#conversation-content').html(str);
});
},300);
}
</script>