1.邮箱：
var re=/^([a-zA-Z0-9_-])+@([a-zA-Z0-9_-])+((\.[a-zA-Z0-9_-]{2,3}){1,2})$/;
if(!re.test(email.val())){
return false;
}
2.第一个字符必须是字母，由4到15个字符组成！
var re=/^([a-zA-Z]{1})+(\S{3,15})$/;
if(!re.test(username)){
return false;
}
3.至少包含一个数字，整个字符串长度大于等于8.
function test_number(){
var str =document.getElementById('inputbox').value;
reg = /(?=\w{8,})^\w*\d\w*$/;
if(!reg.test(str)){
alert("invalid");
}else{
alert("valid");
}
};
4.禁用中文及中文字符：/^[\x00-\xff]+$/
5.校验端口号：/^\d{4,6}$/
6.扩展String的length，中文算2个字节
String.prototype.len = function(){
return this.replace(/[^\x00-\xff]/g,"li").length;
}
var str = "我是yy";
alert(str.len());//display:6
7.校验字符A,由数字、字母、下划线、横线、小数点组成:/^([0-9a-zA-Z_.\-])+$/
8.校验字符B,以字母开头的任意字符,除空格以外的字符:/^([a-zA-Z]{1})+\S+$/
9.IP:/^(d{1,2}|1dd|2[0-4]d|25[0-5]).(d{1,2}|1dd|2[0-4]d|25[0-5]).(d{1,2}|1dd|2[0-4]d|25[0-5]).(d{1,2}|1dd|2[0-4]d|25[0-5])$/
10.手机号码:/^13[0-9]{1}[0-9]{8}$|^15[012356789]{1}[0-9]{8}$|^18[0256789]{1}[0-9]{8}$/
11.电话号码:/^(([0\+]\d{2,3}-)?(0\d{2,3})-)?(\d{7,8})(-(\d{3,}))?$/
12.URL:/^(https?|ftp):\/\/(((([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(%[\da-f]{2})|[!\$&'\(\)\*\+,;=]|:)*@)?(((\d|[1-9]\d|1\d\d|2[0-4]\d|25[0-5])\.(\d|[1-9]\d|1\d\d|2[0-4]\d|25[0-5])\.(\d|[1-9]\d|1\d\d|2[0-4]\d|25[0-5])\.(\d|[1-9]\d|1\d\d|2[0-4]\d|25[0-5]))|((([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])*([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])))\.)+(([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])*([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])))\.?)(:\d*)?)(\/((([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(%[\da-f]{2})|[!\$&'\(\)\*\+,;=]|:|@)+(\/(([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(%[\da-f]{2})|[!\$&'\(\)\*\+,;=]|:|@)*)*)?)?(\?((([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(%[\da-f]{2})|[!\$&'\(\)\*\+,;=]|:|@)|[\uE000-\uF8FF]|\/|\?)*)?(\#((([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(%[\da-f]{2})|[!\$&'\(\)\*\+,;=]|:|@)|\/|\?)*)?$/i