分享程序员开发的那些事...
更新时间：2023-02-19 12:31:36
上面评论中给出的答复不考虑下面的html标签.
Reply given in the above comment is not considering below html tags.
<html>,<body> and <head>
所以这就是我实施要求的方法，它工作正常.
So this is how i implemented the requirement and it is working fine.
var textboxValue = document.getElementById("textbox").value;
var nonHtmlValue = textboxValue.replace(/<[^>]+>/g, '');
if(textboxValue!=nonHtmlValue)
{
alert("HTML is not allowed");
}