JS 验证身份证

function checkIDNumber(pId) {
    var arrVerifyCode = [1, 0, "X", 9, 8, 7, 6, 5, 4, 3, 2];
    var Wi = [7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2];
    var Checker = [1, 9, 8, 7, 6, 5, 4, 3, 2, 1, 1];
    if (pId.length != 15 && pId.length != 18) {
        alert("身份证号必须为15或18位");
        return false;
    }
    var Ai = pId.length == 18 ? pId.substring(0, 17) : pId.slice(0, 6) + "19" + pId.slice(6, 16);
    if (!/^\d+$/.test(Ai)) {
        alert("除最后一位外必须为数字");
        return false;
    }
    var yyyy = Ai.slice(6, 10), mm = Ai.slice(10, 12) - 1, dd = Ai.slice(12, 14)
    var d = new Date(yyyy, mm, dd), now = new Date()
    var year = d.getFullYear(), mon = d.getMonth(), day = d.getDate()
    if (year != yyyy || mon != mm || day != dd || d > now || year < 1900) {
        alert("身份证出生日期输入有误");
        return false;
    }
    for (var i = 0, ret = 0; i < 17; i++) ret += Ai.charAt(i) * Wi[i];
    Ai += arrVerifyCode[ret %= 11];


    if (pId.length == 15 && pId != Ai) {
        alert("输入的身份证号码有误");
        return false;
    }
    if (pId.length == 18 && pId != Ai) {
        alert("输入的身份证号码有误");
        return false;
    }
    return true
}