Php 不显示从数据库返回的值

Php 不显示从数据库返回的值,php,mysql,html,Php,Mysql,Html,我从一个表中得到某一列的和,查询是正确的,但当我试图在一个表中显示它打印为零时。下面是我的刀 public function getTotal_paid($id) { $dbHandler = new dbConfig(); $query="select SUM(payed) from itemsale where custId = $id"; $results = $dbHandler->Query($query); return $results; }

我从一个表中得到某一列的和,查询是正确的,但当我试图在一个表中显示它打印为零时。下面是我的刀

public function getTotal_paid($id)
{
    $dbHandler = new dbConfig();
    $query="select SUM(payed) from itemsale where custId = $id";
    $results = $dbHandler->Query($query);
    return $results;
} // End-Function
以下是我的逻辑

public function getTotal_paid($id)
{
    $objDAO = new itemsaleDAO();
    $results = $objDAO->getTotal_paid($id);
    return $results;
} // End-Function
这是我的首页

<table cellpadding="0" cellspacing="0" border="1" align="right">
<tr><th style="height:10px" class="heading_text">Total Paid</th><th style="height:10px    width:10px" class="heading_text">Total Remaining</th></tr>
<?
include_once($commonLocation.'Logic/itemSaleLogic.php'); 
$var= new itemSale();
$object= new itemSaleLogic();
$object1= array();
$object1[0]= new stdClass;
$object1[0]->custId = $_GET['id'];
$var->payed=$object->getTotal_paid($object1[0]);
//$var->remaining=$object->getTotal_rem(6);
echo $var->payed;

echo "<tr><td class=\"inner_text\">".$var->payed."</td>";
//echo "<td class=\"inner_text\">".$var->remaining."</td></tr>";
?>
</table>
include_once($commonLocation.'Logic/itemSaleLogic.php'); 

$dbHandler = new dbConfig();  // make sure you have your DB object...

$var= new itemSale();

$var->getTotal_paid(intval($_GET['id']));

var_dump($var);    // for debug

echo $var->itemSum;  // to output your sum.. do with what you want!


?>

总付余款

对象$var->payed显示为零(忽略payed的拼写)

这不会简化它吗?看起来你在课堂上以一种奇怪的方式蹦蹦跳跳。未检查或测试,但作为如何改进的示例:

类别项目销售:

public function getTotal_paid($id)
{
    global $dbHandler;    // important! this pulls your DB object in..

    $query="select SUM(payed) as itemSum from itemsale where custId = $id";   // note query change here!

    $results = $dbHandler->Query($query);

    return $results;
}
首页

<table cellpadding="0" cellspacing="0" border="1" align="right">
<tr><th style="height:10px" class="heading_text">Total Paid</th><th style="height:10px    width:10px" class="heading_text">Total Remaining</th></tr>
<?
include_once($commonLocation.'Logic/itemSaleLogic.php'); 
$var= new itemSale();
$object= new itemSaleLogic();
$object1= array();
$object1[0]= new stdClass;
$object1[0]->custId = $_GET['id'];
$var->payed=$object->getTotal_paid($object1[0]);
//$var->remaining=$object->getTotal_rem(6);
echo $var->payed;

echo "<tr><td class=\"inner_text\">".$var->payed."</td>";
//echo "<td class=\"inner_text\">".$var->remaining."</td></tr>";
?>
</table>
include_once($commonLocation.'Logic/itemSaleLogic.php'); 

$dbHandler = new dbConfig();  // make sure you have your DB object...

$var= new itemSale();

$var->getTotal_paid(intval($_GET['id']));

var_dump($var);    // for debug

echo $var->itemSum;  // to output your sum.. do with what you want!


?>

伙计,你不能有两个同名的函数(getTotal_paid)@Tom-如果它们在不同的类中,他可以,很可能是这样,否则PHP会抛出一个解析错误。你的第二个函数在类中吗?无法从你的例子中理解你是如何接近的。您知道在前端页面中硬编码了6作为id吗?请尝试“var_dump($dbHandler->Query($Query));结果是记录集吗?是查询句柄资源吗?或者别的什么?什么是dbConfig->Query()?我有一个文件夹模型,其中所有的数据库工作都完成了,这是DAO部分(第一个total_paid函数),它返回到逻辑文件夹(第二个函数),然后返回到前端层。你可以说它的三层逻辑部分只是一个包装类型var_dump($var)做什么?你需要学习var_dump()。。。。。。它将输出您的对象/数组的内容,这样您就可以消除bug并了解发生了什么!尝试将var_dump()添加到当前脚本中,并将转储数据粘贴到此处,以便我们可以看到。。。。您的数据将在那里的某个地方,但很确定您的查询也需要注意