常用js验证

//字符长短 用户名
function check_name()
{
var upname= document.getElementById("txt_name").value;
var re =new RegExp("^.{5,50}$");
var arr;
if((arr = re.exec(upname)) == null)
{
document.getElementById("err_name").className = "style5";
document.getElementById("txt_name").value = "";
return;
}
document.getElementById("err_name").className = "style4";
return true;
}

//字符长短 密码
function check_pwd()
{
var upoldpwd= document.getElementById("txt_pwd").value;
var re =new RegExp("^.{5,50}$");
var arr;
if((arr = re.exec(upoldpwd)) == null)
{
document.getElementById("err_pwd").className = "style5";
document.getElementById("txt_pwd").value = "";
return;
}
document.getElementById("err_pwd").className = "style4";
return true;
}

//是否重复 验证密码
function check_two_pwd()
{
var tit1= document.getElementById("txt_pwd").value;
var tit2= document.getElementById("txt_check_pwd").value;

if(tit1.length == "" || tit1 != tit2)
{
document.getElementById("err_checkpwd").className = "style5";
document.getElementById("txt_pwd").value = "";
document.getElementById("txt_check_pwd").value = "";
return;
}
document.getElementById("err_checkpwd").className = "style4";
return true;
}

//E－mail 验证mail
function check_mail()
{
var str= document.getElementById("txt_mail").value;
var sReg = /[_a-zA-Z\d\-\.]+@[_a-zA-Z\d\-]+(\.[_a-zA-Z\d\-]+)+$/;
if (!sReg.test(str))
{
document.getElementById("err_mail").className = "style5";
document.getElementById("txt_mail").value = "";
return;
}

document.getElementById("err_mail").className = "style4";
return true;
}

//是否数字 验证桌号
function check_table()
{
var srange = document.getElementById("txt_table").value;
var patrn=/^[0-9]{1,20}$/;
if(srange == null || srange == "" || !patrn.exec(srange) || srange.indexOf('0') == 0)
{
document.getElementById("err_checktable").className = "style5";
document.getElementById("txt_table").value = "";
return false;
}

document.getElementById("err_checktable").className = "style4";
return true;
}