锋利的js之妈妈再也不用担心我找错钱了

用js实现收银功能。

 <!DOCTYPE html>
 <html xmlns="http://www.w3.org/1999/xhtml">
 <head>
     <title>xx超市收银系统</title>
     <script src="http://libs.baidu.com/jquery/1.10.2/jquery.min.js">
     </script>
     <script type="text/javascript">
         $(function () {
             $('form').submit(function () {
                 var payable = Number($('#txtPayable').val());//应付
                 var payment = Number($('#txtPayment').val());//实付
                 if (payable === payment) {
                     $('#tdPocket').text(0);
                 } else if (payable > payment) {
                     $('#tdPocket').text('您还需再支付' + (payable*10 - payment*10)/10 + '元！');
                 } else {//需要找零
                     var yuan = [100, 50, 20, 10, 5, 1];
                     var jiao = [5, 2, 1];
                     var msg = '';
                     var payableYuan = parseInt(payable);
                     var paymentYuan = parseInt(payment);
                     var pocketYuan = paymentYuan - payableYuan;//找零元
                     var surplus = pocketYuan;
                     $(yuan).each(function() {
                             if (surplus >= this) {
                                 var count = parseInt(surplus / this);
                                 msg += this + '元' + count + '张';
                                 surplus -= count * this;
                             }
                     });
                     //在js中10.2-10.1=0.09999999999999964，防止小数误差，需要*10
                     var pocketJiao = parseInt(((payment * 10) - (payable * 10)) - (pocketYuan * 10));//找零角
                     surplus = pocketJiao;
                     $(jiao).each(function () {
                         if (surplus >= this) {
                             var count = parseInt(surplus / this);
                             msg += this + '角' + count + '张';
                             surplus -= count * this;
                         }
                     });
                     msg += '共' + pocketYuan + '.' + pocketJiao + '元';
                     $('#tdPocket').text(msg);
                 }
                 return false;
             });
         });
     </script>
     <style type="text/css">
         table {
             border: 1px solid #0000cd;
         }         td {
             padding: 2px;
         }         .right {
             text-align: right;
         }          .left {
             text-align: left;
             width: 50px;
         }         .center {
             text-align: center;
         }
     </style>
 </head>
 <body>
     <form>
         <table border="1" cellpadding="0" cellspacing="0">
             <tr>
                 <td class="right">应付：</td>
                 <td class="left"><input type="number" id="txtPayable" min="0" step="any" /></td>
             </tr>
             <tr>
                 <td class="right">实付：</td>
                 <td class="left"><input type="number" id="txtPayment" min="0" step="any" /></td>
             </tr>
             <tr>
                 <td class="right">找零：</td>
                 <td class="left" id="tdPocket"></td>
             </tr>
             <tr>
                 <td colspan="2" class="center"><input type="submit" value="计算" id="btnCalc" /></td>
             </tr>
         </table>
     </form>
 </body>
 </html>