javascript实现根据身份证号读取相关信息

<div style="padding:20px 40px;">
        <h1 style="font-size:20px;color:#999;">身份证查询</h1>
        <input type="text" placeholder="输入身份证号" id="code">
        <input type="button" value="查询" id="btn">
        <p id="home"><strong>籍&nbsp;&nbsp;&nbsp;&nbsp;贯：</strong><span></span></p>
        <p id="birthday"><strong>出生日期：</strong><span></span></p>
        <p id="sex"><strong>性&nbsp;&nbsp;&nbsp;&nbsp;别：</strong><span></span></p>
    </div>
    <script type="text/javascript">
        //去掉字符串头尾空格  
        var home='',birthday='',sex='';
        function trim(str) {  
            return str.replace(/^\s*|\s*$/g, "");  
        }
        //验证身份证
        function IdentityCodeValid(code) {
            code=trim(code);
            var city={11:"北京",12:"天津",13:"河北",14:"山西",15:"内蒙古",21:"辽宁",22:"吉林",23:"黑龙江 ",31:"上海",32:"江苏",33:"浙江",34:"安徽",35:"福建",36:"江西",37:"山东",41:"河南",42:"湖北 ",43:"湖南",44:"广东",45:"广西",46:"海南",50:"重庆",51:"四川",52:"贵州",53:"云南",54:"西藏 ",61:"陕西",62:"甘肃",63:"青海",64:"宁夏",65:"新疆",71:"台湾",81:"香港",82:"澳门"};   
            if(!code || !/^\d{6}(18|19|20)?\d{2}(0[1-9]|1[012])(0[1-9]|[12]\d|3[01])\d{3}(\d|X)$/i.test(code)){
                alert("身份证号格式错误");
                home='',birthday='',sex='';
                return false;
            }
            if(!city[code.substring(0,2)]){
                alert("地址编码错误");
                home='',birthday='',sex='';
                return false;
            }
            if(code.length == 18){    //18位身份证需要验证最后一位校验位
                var codeArr = code.split('');       
                var factor = [ 7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2 ];    //加权因子               
                var parity = [ 1, 0, 'X', 9, 8, 7, 6, 5, 4, 3, 2 ];                        //校验位
                var sum = 0;
                for (var i = 0; i < 17; i++){
                    sum += codeArr[i] * factor[i];
                }
                if(parity[sum % 11] != codeArr[17]){
                    alert("校验位错误");
                    home='',birthday='',sex='';
                    return false;
                }               
            }
            //省份
            home = city[code.substring(0,2)];   
            //生日
            birthday = code.substring(6,10)+'年'+code.substring(10,12)+'月'+code.substring(12,14)+'日';
            //性别
            if(code.length==15){
                sex = code.substring(14,15)%2==0 ? '女':'男';
            }else if(code.length==18){
                sex = code.substring(14,17)%2==0 ? '女':'男';
            }
        }
           //输出结果
        document.querySelector('#btn').onclick=function(){
            var code=document.querySelector('#code').value;
            IdentityCodeValid(code);
            document.querySelector('#home span').innerHTML=home;
            document.querySelector('#birthday span').innerHTML=birthday;
            document.querySelector('#sex span').innerHTML=sex;
        }
    </script>