function check()
{
if (document.form1.userName.value == "")
{
layer.msg('Can not be empty');
document.form1.userName.focus();
return (false);//停止往下运行
};
//验证邮箱
var email = new RegExp("^[a-z0-9]+([._\\-]*[a-z0-9])*@([a-z0-9]+[-a-z0-9]*[a-z0-9]+.){1,63}[a-z0-9]+$"); //正则表达式
var userName = document.getElementById("userName"); //要验证的对象，表单的input的id
if(!email.test(userName.value)){ //正则验证不通过，格式不对
layer.msg('Incorrect mailbox format');
document.form1.userName.focus();
return (false);//停止往下运行
}
};