javascript身份证检验正则表达式(支持15,18位及省份差别)

checkCard = function()
{
    var card = document.getElementById('card_no').value;
    //是否为空
    if(card === '')
    {
        alert('请输入身份证号，身份证号不能为空');
        document.getElementById('card_no').focus;
        return false;
    }
    //校验长度，类型
    if(isCardNo(card) === false)
    {
        alert('您输入的身份证号码不正确，请重新输入');
        document.getElementById('card_no').focus;
        return false;
    }
    //检查省份
    if(checkProvince(card) === false)
    {
        alert('您输入的身份证号码不正确,请重新输入');
        document.getElementById('card_no').focus;
        return false;
    }
    //校验生日
    if(checkBirthday(card) === false)
    {
        alert('您输入的身份证号码生日不正确,请重新输入');
        document.getElementById('card_no').focus();
        return false;
    }
    //检验位的检测
    if(checkParity(card) === false)
    {
        alert('您的身份证校验位不正确,请重新输入');
        document.getElementById('card_no').focus();
        return false;
    }
    alert('OK');
    return true;
};

//检查号码是否符合规范，包括长度，类型
isCardNo = function(card)
{
    //身份证号码为15位或者18位，15位时全为数字，18位前17位为数字，最后一位是校验位，可能为数字或字符X
    var reg = /(^d{15}$)|(^d{17}(d|X)$)/;
    if(reg.test(card) === false)
    {
        alert("demo");
        return false;
    }

    return true;
};

//取身份证前两位,校验省份
checkProvince = function(card)
{
    var province = card.substr(0,2);
    if(vcity[province] == undefined)
    {
        return false;
    }
    return true;
};

//检查生日是否正确
checkBirthday = function(card)
{
    var len = card.length;
    //身份证15位时，次序为省（3位）市（3位）年（2位）月（2位）日（2位）校验位（3位），皆为数字
    if(len == '15')
    {
        var re_fifteen = /^(d{6})(d{2})(d{2})(d{2})(d{3})$/;
        var arr_data = card.match(re_fifteen);
        var year = arr_data[2];
        var month = arr_data[3];
        var day = arr_data[4];
        var birthday = new Date('19'+year+'/'+month+'/'+day);
        return verifyBirthday('19'+year,month,day,birthday);
    }
    //身份证18位时，次序为省（3位）市（3位）年（4位）月（2位）日（2位）校验位（4位），校验位末尾可能为X
    if(len == '18')
    {
        var re_eighteen = /^(d{6})(d{4})(d{2})(d{2})(d{3})([0-9]|X)$/;
        var arr_data = card.match(re_eighteen);
        var year = arr_data[2];
        var month = arr_data[3];
        var day = arr_data[4];
        var birthday = new Date(year+'/'+month+'/'+day);
        return verifyBirthday(year,month,day,birthday);
    }
    return false;
};

//校验日期
verifyBirthday = function(year,month,day,birthday)
{
    var now = new Date();
    var now_year = now.getFullYear();
    //年月日是否合理
    if(birthday.getFullYear() == year && (birthday.getMonth() + 1) == month && birthday.getDate() == day)
    {
        //判断年份的范围（3岁到100岁之间)
        var time = now_year - year;
        if(time >= 3 && time <= 100)
        {
            return true;
        }
        return false;
    }
    return false;
};

//校验位的检测
checkParity = function(card)
{
    //15位转18位
    card = changeFivteenToEighteen(card);
    var len = card.length;
    if(len == '18')
    {
        var arrInt = new Array(7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2);
        var arrCh = new Array('1', '0', 'X', '9', '8', '7', '6', '5', '4', '3', '2');
        var cardTemp = 0, i, valnum;
        for(i = 0; i < 17; i ++)
        {
            cardTemp += card.substr(i, 1) * arrInt[i];
        }
        valnum = arrCh[cardTemp % 11];
        if (valnum == card.substr(17, 1))
        {
            return true;
        }
        return false;
    }
    return false;
};

//15位转18位身份证号
changeFivteenToEighteen = function(card)
{
    if(card.length == '15')
    {
        var arrInt = new Array(7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2);
        var arrCh = new Array('1', '0', 'X', '9', '8', '7', '6', '5', '4', '3', '2');
        var cardTemp = 0, i;  
        card = card.substr(0, 6) + '19' + card.substr(6, card.length - 6);
        for(i = 0; i < 17; i ++)
        {
            cardTemp += card.substr(i, 1) * arrInt[i];
        }
        card += arrCh[cardTemp % 11];
        return card;
    }
    return card;
};