1.email验证
代码:
<script type="text/javascript"> function validate_required(field,alerttxt) { with(field) { if(value==null||value=="") { alert(alerttxt);return false; } else { return true; } } } function validate_form(thisform) { with(thisform) { if(validate_required(email,"Email must be filled out!")==false) { email.focus();return false; } } } </script>用法:
<form action="#" onsubmit="validate_form(this)" method="post"> Email:<input type="text" name="email" size="30"> <input type="submit" value="Submit"> </form>
2.getElementById getElementsByTagName 的使用
getElementById