Question

如何在javascript限制文本框中只能输入网址

Answer 1

<input type="text" id="demo"/><span id="output"></span>
<script type="text/javascript">
var urlReg = /^(https?:\/\/)?([\da-z\.-]+)\.([a-z\.]{2,6})([\/\w \.-]*)*\/?$/;
setInterval(function(){
if(document.getElementById("demo").value.match(urlReg) == null){
document.getElementById("output").innerHTML = "only url allowed";
}else{
document.getElementById("output").innerHTML = "";
}
},500);
</script>

如果格式不对就会出现only url allowed的字样,输入正确后就会消失

Answer 2

用正则表达式，具体怎么写 你用google一搜就知道了