在最近学习的经典模块中有使用JavaScript实现购物车自动刷新商品数量和商品价格的功能；经过我的一番研究后把代码整理出来；
由于这个例子中并没有使用到数据库，定义了一个数组作为数据源，代码如下
<?php
$shopcar=array(
array("0","手机","20","100","98","9.8"),
array("1","电脑","25","120","88","9"),
array("2","汽车","19","200","180","9"),
array("3","香蕉","10","2","1.8","9"),
array("4","苹果","5","5","4.8","9"),
);
?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<table border="0" cellspacing="0" cellpadding="0" align="center">
<form id="myshopcar" name="myshopcar" method="post" action="#">
<tr>
<td height="30" colspan="7" align="center" valign="middle" class="first">我的购物车</td>
</tr>
<tr>
<td width="35" height="25" align="center" valign="middle" class="left"> </td>
<td width="100" height="25" align="center" valign="middle" class="center">商品名称</td>
<td width="100" height="25" align="center" valign="middle" class="center">购买数量</td>
<td width="100" height="25" align="center" valign="middle" class="center">市场价格</td>
<td width="100" height="25" align="center" valign="middle" class="center">会员价格</td>
<td width="100" height="25" align="center" valign="middle" class="center">折扣率</td>
<td width="100" height="25" align="center" valign="middle" class="right">合计</td>
</tr>
<?php foreach ($shopcar as $key => $value) { ?>
<tr>
<td height="25" align="center" valign="middle" class="left"><input id="chk" name="chk[]" type="checkbox" value="<?php echo $value[0]; ?>"></td>
<td height="25" align="center" valign="middle" class="center"><div id = "c_name<?php echo $value[0]; ?>"> <?php echo $value[1]; ?></div></td>
<td height="25" align="center" valign="middle" class="center">
<input id="cnum<?php echo $value[0]; ?>" name="cnum<?php echo $value[0]; ?>" type="text" class="shorttxt" value="<?php echo $value[2]; ?>" onkeyup="cvp(<?php echo $value[0]; ?>,<?php echo $value[4]; ?>,<?php echo count($shopcar) ?>)"></td>
<td height="25" align="center" valign="middle" class="center"><div id="m_price<?php echo $value[0]; ?>"> <?php echo $value[3]; ?></div></td>
<td height="25" align="center" valign="middle" class="center"><div id="v_price<?php echo $value[0]; ?>"> <?php echo $value[4]; ?></div></td>
<td height="25" align="center" valign="middle" class="center"><div id="fold<?php echo $value[0]; ?>"> <?php echo $value[5]; ?></div></td>
<td height="25" align="center" valign="middle" class="right"><div id="total<?php echo $value[0]; ?>"> <?php echo $value[2]*$value[4]; ?></div></td>
<tr>
<?php } ?>
<td height="25" colspan="3" align="left" valign="middle">
<a href="#" onclick="return alldel(myshopcar)">全选</a> <a href="#" onclick="return overdel(myshopcar);">反选</a>
<input type="button" value="删除选择" class="btn" style="border-color: #FFFFFF;" onClick = 'return del(myshopcar);'> </td>
<td height="25" align="center" valign="middle"><input id="cont" name="cont" type="button" class="btn" value="去数据库修改" onclick="return conshop(myshopcar)" /></td>
<td height="25" align="center" valign="middle"><input id="uid" name="uid" type="hidden" value="tang" ><input id="settle" name="settle" type="button" class="btn" value="去收银台" onclick="return formset(form)" /></td>
<td height="25" colspan="2" align="right" valign="middle"><div id='sum'>共计7622 元</div></td>
</tr>
</form>
</table>
</body>
</html>
然后是最主要的JavaScript脚本，实现自动刷新的功能代码如下：
实现商品删除代码：
<script>
/* 删除记录 */
function del(form){
if(!window.confirm('是否要删除数据??')){
}else{
var leng = form.chk.length;//返回复选框的长度
if(leng==undefined){
if(!form.chk.checked){
alert('请选取要删除数据!');
}else{//如果只有一个复选框，而且处于选中状态
rd = form.chk.value;//将复选框的value值直接赋给变量rd
var url = 'test.php?rd='+rd;//根据rd生成url
xmlhttp.open("GET",url,true);
xmlhttp.onreadystatechange = delnow;//调用delnow函数
xmlhttp.send(null);
}
}else{ //如果复选框为多个
var rd=new Array();//声明数组
var j = 0;
for( var i = 0; i < leng; i++){//循环检查复选框状态
if(form.chk[i].checked){
rd[j++] = form.chk[i].value;//将被选中的复选框的value值存到rd内
}
}
if(rd == ''){
alert('请选取要删除数据!');
}else{
var url = "test.php?rd="+rd;
alert(url);
xmlhttp.open("GET",url,true);
xmlhttp.onreadystatechange = delnow;
xmlhttp.send(null);
}
}
}
return false;
}
function delnow(){
if(xmlhttp.readyState == 4&&xmlhttp.status == 200){
var msg = xmlhttp.responseText;
if(msg != '1'){
alert('删除失败'+msg);
}else{
alert('删除成功');
location=('?page_type=shopcar');
}
}
}
//全部选择/取消
function alldel(form){
var leng = form.chk.length;
if(leng==undefined){
if(!form.chk.checked)
form.chk.checked=true;
}else{
for( var i = 0; i < leng; i++)
{
if(!form.chk[i].checked)
form.chk[i].checked = true;
}
}
return false;
}
// 反选
function overdel(form){
var leng = form.chk.length;
if(leng==undefined){
if(!form.chk.checked)
form.chk.checked=true;
else
form.chk.checked=false;
}else{
for( var i = 0; i < leng; i++)
{
if(!form.chk[i].checked)
form.chk[i].checked = true;
else
form.chk[i].checked = false;
}
}
return false;
}
实现自动刷新总金额代码：
//自动刷新总金额
// key商品id
// vpr商品单价
// shoparr商品数量
function cvp(key,vpr,shoparr){
var n_pre = 'total';//获取div标签的id前缀
var num = 'cnum'+key.toString();//根据key值生成文本域的id值
var total = n_pre+key.toString();//根据key值生成的div标签的id值
var t_number = document.getElementById(num).value;//获取输入的商品数量
var ttl = t_number * vpr;//根据商品数量和单价，计算商品金额
document.getElementById(total).innerHTML = ttl;//计算商品总金额
var sm = 0; //所有商品总金额，初始为0
for(var i = 0; i < shoparr; i++){//根据商品种类数，循环得到其他商品金额
var aaa = document.getElementById(n_pre+i.toString()).innerText;
sm += parseInt(aaa);//将所有商品金额累加
}
document.getElementById('sum').innerHTML = '共计：'+sm+' 元';
}
//更改商品数量
function conshop(form){
var n_pre = 'cnum';//获取商品数量文本域前缀
var lang = form.chk.length;//获取复选框的数量
if(lang == undefined){//如果只有一个复选框，那么将商品id和商品数量直接保存到变量中
var fst = form.chk.value;
var snd = form.cnum0.value;
}else{//否则将商品id和对应的商品数量保存到两个相应数组中
var fst= new Array();//商品id数组
var snd = new Array();//商品数量数组
for(var i = 0; i < lang; i++){//循环获取复选框的value值和商品数量文本框的value值
var nm = n_pre+i.toString();
var stmp = document.getElementById(nm).value;
if(stmp == '' || isNaN(stmp)){
alert('不允许为空、必须为数字');//对商品数量文本框判断
document.getElementById(nm).select();
return false;
}
snd[i] = stmp;
var ftmp = form.chk[i].value;
fst[i] = ftmp;
}
}
var url = 'test.php?fst='+fst+'&snd='+snd;
alert(url);
xmlhttp.open("GET",url,true);
xmlhttp.onreadystatechange = updatecar;//调用updatecar函数
xmlhttp.send(null);
}
function updatecar(){//对xmlhttp对象返回值进行处理
if(xmlhttp.readyState == 4){
var msg = xmlhttp.responseText;
if(msg == '1'){
location='index.php';
}else{
alert('操作失败'+msg);
}
}
}
实现显示订单代码：
// 显示订单
function formset(form){
var uid = form.uid.value;//获取订单提交人的名称
var n_pre = 'cnum'; //商品数量文本前缀
var lang = form.chk.length; //复选框个数
if(lang == undefined){ // 如果复选框只有一个
var fst = form.chk.value; //商品id
var snd = form.cnum0.value; //购买数量
}else{// 如果复选框多个
var fst= new Array();
var snd = new Array();
for(var i = 0; i < lang; i++){// 循环获取商品数量和商品id
var nm = n_pre+i.toString();
var stmp = document.getElementById(nm).value;
if(stmp == '' || isNaN(stmp)){
alert('不允许为空、必须为数字');
document.getElementById(nm).select();
return false;
}
snd[i] = stmp;
var ftmp = form.chk[i].value;
fst[i] = ftmp;
}
}
alert('test.php?uid='+uid+'&fst='+fst+'&snd='+snd);
// open('test.php?uid='+uid+'&fst='+fst+'&snd='+snd,'_blank','width=650 height=300',false);
}
</script>
这里实现数据处理页面的代码参考简单购物车
如在实现商品删除功能代码如下
<?php
session_start();
header ( "Content-type: text/html; charset=UTF-8" ); //设置文件编码格式
require("system/system.inc.php"); //包含配置文件
/* xmlhttp返回参数 */
$reback = '0';
/* 将传过来的变量以逗号分割 */
$commid = explode(',',$_GET['rd']);
/* 更新数据库所需数组 */
$newshop = array();
/* 查找当前用户 */
$sql = "select id,shopping from tb_user where name = '".$_SESSION['member']."'";
$rst = $admindb->ExecSQL($sql,$conn);
if($rst==false){
$reback = '2';
}else{
/* 将shopping字段用@分割 */
if(!empty($rst[0]['shopping'])){
$tmpshop = array();
$shopping = explode('@',$rst[0]['shopping']);
foreach($shopping as $ky => $vl){
$tmp = explode(',',$vl);
$boo = false;
foreach($commid as $value){
if($value == $tmp[0]){
$boo = true;
}
}
if(!$boo){
$tmpshop[$ky] = $vl;
}
}
if(!empty($tmpshop)){
$update = "update tb_user set shopping='".implode('@',$tmpshop)."' where name = '".$_SESSION['member']."'";
}else{
$update = "update tb_user set shopping='' where name = '".$_SESSION['member']."'";
}
$shop = $admindb->ExecSQL($update,$conn);
if($shop){
$reback = 1;
}else{
$reback = 3;
}
}
}
echo $reback;
?>
去数据库修改代码如下
<?php
session_start();
header ( "Content-type: text/html; charset=UTF-8" ); //设置文件编码格式
require("system/system.inc.php"); //包含配置文件
$sql = "select id,shopping from tb_user where name = '".$_SESSION['member']."'";
$rst = $admindb->ExecSQL($sql,$conn);//返回热二维数组
$reback = '0';
$changecar = array();
if(isset($_GET['fst']) && isset($_GET['snd'])){
$fst = $_GET['fst'];//商品id
$snd = $_GET['snd'];//商品数量
$farr = explode(',',$fst);
$sarr = explode(',',$snd);
$upcar = array();
for($i = 0; $i < count($farr); $i++){
$upcar[$i] = $farr[$i].','.$sarr[$i];
}
if(count($farr) > 1){
$update = "update tb_user set shopping='".implode('@',$upcar)."' where name = '".$_SESSION['member']."'";
}else{
$update = "update tb_user set shopping='".$upcar[0]."' where name = '".$_SESSION['member']."'";
}
$shop = $admindb->ExecSQL($update,$conn);
if($shop){
$reback = 1;
}else{
$reback = 2;
}
}
echo $reback;
?>
代码下载链接 附上一句诗句：海到尽头天作岸，山登绝顶我为峰。加油！