验证身份证的合法性

function isIDCard(obj) {
    var aCity = {
        11: "北京",
        12: "天津",
        13: "河北",
        14: "山西",
        15: "内蒙古",
        21: "辽宁",
        22: "吉林",
        23: "黑龙 江",
        31: "上海",
        32: "江苏",
        33: "浙江",
        34: "安徽",
        35: "福建",
        36: "江西",
        37: "山东",
        41: "河南",
        42: "湖 北",
        43: "湖南",
        44: "广东",
        45: "广西",
        46: "海南",
        50: "重庆",
        51: "四川",
        52: "贵州",
        53: "云南",
        54: "西 藏",
        61: "陕西",
        62: "甘肃",
        63: "青海",
        64: "宁夏",
        65: "新疆",
        71: "台湾",
        81: "香港",
        82: "澳门",
        91: "国 外"
    };
    var iSum = 0;
    var strIDno = obj;
    var idCardLength = strIDno.length;
    if (!/^\d{17}(\d|x)$/i.test(strIDno) && !/^\d{15}$/i.test(strIDno))
    {
        layer.alert('输入的身份证号长度不对，或者号码不符合规定<br>15位号码应全为数字，18位号码末位可以为数字或X',{icon:2});
        return false;
    }
    if (aCity[parseInt(strIDno.substr(0, 2))] == null) {
        layer.alert('无效身份证号码，请确认',{icon:2});
        return false;// 非法地区
    }

    // 15位身份证转换为18位
    if (idCardLength == 15)
    {
        sBirthday = "19" + strIDno.substr(6, 2) + "-" + Number(strIDno.substr(8, 2)) + "-" + Number(strIDno.substr(10, 2));
        var d = new Date(sBirthday.replace(/-/g, "/"))
        var dd = d.getFullYear().toString() + "-" + (d.getMonth() + 1) + "-" + d.getDate();
        if (sBirthday != dd) {
            layer.alert('身份证号码格式输入错误，生日错误',{icon:2});
            return false; //非法生日
        }
        strIDno = strIDno.substring(0, 6) + "19" + strIDno.substring(6, 15);
        strIDno = strIDno + GetVerifyBit(strIDno);
    }

    // 判断是否大于2078年，小于1900年
    var year = strIDno.substring(6, 10);
    if (year < 1900 || year > 2078) {
        layer.alert('身份证号码格式输入错误，年份错误',{icon:2});
        return false;//非法生日
    }

    //18位身份证处理
    //在后面的运算中x相当于数字10,所以转换成a
    strIDno = strIDno.replace(/x$/i, "a");
    sBirthday = strIDno.substr(6, 4) + "-" + Number(strIDno.substr(10, 2)) + "-" + Number(strIDno.substr(12, 2));
    var d = new Date(sBirthday.replace(/-/g, "/"))
    if (sBirthday != (d.getFullYear() + "-" + (d.getMonth() + 1) + "-" + d.getDate())) {
        layer.alert('身份证号码格式输入错误，生日错误',{icon:2});
        return false; //非法生日
    }
    // 身份证编码规范验证
    for (var i = 17; i >= 0; i --)
        iSum += (Math.pow(2, i) % 11) * parseInt(strIDno.charAt(17 - i), 11);
    if (iSum % 11 != 1) {
        layer.alert('身份证号码无效，请确认',{icon:2});
        return false;// 非法身份证号
    }

    // 判断是否屏蔽身份证
    var words = new Array();
    words = new Array("11111119111111111", "12121219121212121");
    for (var k = 0; k < words.length; k++) {
        if (strIDno.indexOf(words[k]) != -1) {
            return false;
        }
    }
    //return true;
}