<body>
<textarea id="divt">123456789</textarea>
</body>
<script type="text/javascript">
window.onload = function(event){
var div = document.getElementById('divt');
//创建选择区域
if(div.createTextRange){//IE浏览器
var range = div.createTextRange();
range.moveEnd("character",8);
range.moveStart("character", 3);
range.select();
}else{
div.setSelectionRange(3,8);
div.focus();
}
};
</script>
</html>