<html><head><title><a href='http://js.zz5u.net'><u>JavaScript</u></a>用正则验证IP地址格式是否正确</title></head><body><script language="javascript">function f_check_IP() { var ip = document.getElementById('reg_ip').value; var re=/^(\d+)\.(\d+)\.(\d+)\.(\d+)$/;//正则表达式 if(re.test(ip)) { if( RegExp.$1<256 && RegExp.$2<256 && RegExp.$3<256 && RegExp.$4<256) return true; } alert("IP有误！"); return false; }</script><form method="post" action="" οnsubmit="return f_check_IP()">您的IP：<input type="text" id="reg_ip" name="reg_ip"><input type="submit" name="submit" value="提交"></form><br /></body></html>
转载于:https://www.cnblogs.com/gongyuit/p/5485936.html
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