问题
I have a problem with trying to iterate over the amount of results returned in a query,I have a database table called Cart with the following fields:
ItemCode //Unique Code of Item
ItemDesc //Description / Name ofItem
ItemUnitPrice //Unit Price for Item
ItemCategory //Category of Item e.g. Books, CD, DVD etc...
Quantity //Quantity of Item(s) in cart
I want to loop over all the records displayed in my display.php (which simply prints all the data in the Cart table) and then multiply the ItemUnitPrice by the Quantity for every item and store it in a variable to store the total price for everything contained in display.php.
I want something like this:
LOOP
$Total= $ItemUnitPrice * $Quantity;
END LOOP
I am using MySQL and I'm not too sure how I should loop to get the total for each and every item.
So in a nutshell I want to find the total (ItemUnitPrice * Quantity) for each and every item in the database table and store it in a variable.
EDIT:
$query="SELECT * FROM Cart";
$result=mysql_query($query);
$num=mysql_num_rows($result);
$cartTotalPrice = 0;
while($row = mysql_fetch_assoc($result))
{
$cartTotalPrice += ($row['itemUnitPrice']*$row['Quantity']);
}
$_SESSION['totalCost'] = $cartTotalPrice;
mysql_close();
session_start();
echo "<b><center> Islamic Book Store - Your Shopping Cart </b><br/><br/>";
$i=0;
echo "<table border=1><tr><th>Item Code</th><th>Item Desc,</th>";
echo "<th> Item Unit Price</th><th>Item Category</th><th>Quantity</th><th>Image</th> <th>Update Quantity</th></tr>";
while ($i < $num)
{
$ItemCode = mysql_result($result,$i,"ItemCode");
$ItemDesc = mysql_result($result,$i,"ItemDesc");
$ItemUnitPrice = mysql_result($result,$i,"ItemUnitPrice");
$ItemCategory = mysql_result($result,$i,"ItemCategory");
$Quantity = mysql_result($result,$i,"Quantity");
echo "<tr><td align=center>$ItemCode</td><td align=center>$ItemDesc</td>";
echo "<td align=center>£$ItemUnitPrice</td>";
echo "<td align=center>$ItemCategory</td><td align=center>$Quantity</td>";
$i++;
}
echo "</table><center>";
echo "$num Item(s) found.";
echo "<br/><br/><center><form action = 'clear.php'><input type='submit' value='Clear'> </form></center>";
?>
<html>
<form action="https://www.paypal.com/cgi-bin/webscr" method="post" target="_BLANK">
<input type="hidden" name="cmd" value="_xclick" />
<input type="hidden" name="business" value="email@example.com" />
<input type="hidden" name="item_name" value="<? echo $ItemDesc ?>" />
<input type="hidden" name="item_number" value="TEST ITEM NUMBER" />
<input type="hidden" name="amount" value="<? echo $cartTotalPrice ?>" />
<input type="hidden" name="currency_code" value="GBP" />
<input type="hidden" name="lc" value="GB" />
<input type="hidden" name="bn" value="PP-BuyNowBF" />
<input src="paypal/purchase.png" name="Submit" type="image" value="purchase" alt="Purchase" />
</form>
</html>
回答1:
First of all, get out of the habit of using mysql_* functions! Use PDO or mysqli.
Why shouldn't I use mysql_* functions in PHP?
http://php.net/pdo
Secondly, I'm sad to tell you, your code is completely wrong!
session_start();
$query = "SELECT * FROM Cart";
$result = mysql_query($query);
$num = mysql_num_rows($result);
$cartTotalPrice = 0;
while($row = mysql_fetch_assoc($result))
{
$cartTotalPrice += ($row['itemUnitPrice']*$row['Quantity']);
echo "<tr><td align=center>{$row['itemCode']}</td><td align=center>{$row['ItemDesc']}</td>";
echo "<td align=center>{$row['ItemUnitPrice']}</td>";
echo "<td align=center>{$row['$ItemCategory']}</td><td align=center>{$row['$Quantity']}</td></tr>";
}
$_SESSION['totalCost'] = $cartTotalPrice;
// $_SESSION['totalCost'] is now available on every page (as long as you use start_session() before any output)
mysql_close();
回答2:
Try the below code I hope it works, I made the corrections and mentioned them in comments:
$query="SELECT * FROM Cart";
$result=mysql_query($query);
$num=mysql_num_rows($result);
$cartTotalPrice = 0;
while($row = mysql_fetch_assoc($result))
{
$cartTotalPrice += ($row['itemUnitPrice']*$row['Quantity']);
}
session_start();
$_SESSION['totalCost'] = $cartTotalPrice;
// mysql_close(); // here you are closing your mysql connection before using mysql_result refer to the example in http://php.net/manual/en/function.mysql-result.php
// session_start(); // session start should go above you dont need session if the whole script is in the same page. no need to save the variable to session
echo "<b><center> Islamic Book Store - Your Shopping Cart </b><br/><br/>";
$i=0;
echo "<table border=1><tr><th>Item Code</th><th>Item Desc,</th>";
echo "<th> Item Unit Price</th><th>Item Category</th><th>Quantity</th><th>Image</th> <th>Update Quantity</th></tr>";
while ($i < $num)
{
$ItemCode = mysql_result($result,$i,"ItemCode");
$ItemDesc = mysql_result($result,$i,"ItemDesc");
$ItemUnitPrice = mysql_result($result,$i,"ItemUnitPrice");
$ItemCategory = mysql_result($result,$i,"ItemCategory");
$Quantity = mysql_result($result,$i,"Quantity");
echo "<tr><td align=center>$ItemCode</td><td align=center>$ItemDesc</td>";
echo "<td align=center>£$ItemUnitPrice</td>";
echo "<td align=center>$ItemCategory</td><td align=center>$Quantity</td>";
$i++;
}
echo "</table><center>";
echo "$num Item(s) found.";
echo "<br/><br/><center><form action = 'clear.php'><input type='submit' value='Clear'> </form></center>";
mysql_close();
?>
<html>
<form action="https://www.paypal.com/cgi-bin/webscr" method="post" target="_BLANK">
<input type="hidden" name="cmd" value="_xclick" />
<input type="hidden" name="business" value="info@asianweddingservices.org" />
<input type="hidden" name="item_name" value="<? echo $ItemDesc ?>" />
<input type="hidden" name="item_number" value="TEST ITEM NUMBER" />
<input type="hidden" name="amount" value="<? echo $cartTotalPrice ?>" />
<input type="hidden" name="currency_code" value="GBP" />
<input type="hidden" name="lc" value="GB" />
<input type="hidden" name="bn" value="PP-BuyNowBF" />
<input src="paypal/purchase.png" name="Submit" type="image" value="purchase" alt="Purchase" />
</form>
</html>
来源：https://stackoverflow.com/questions/16823472/iterate-over-database-table-values