Question

我的表单包含输入字段item id，staff id和quantity。我想在按 issue 时更新表格。我想要我提交的值，即只有当它小于或等于目标表中已有的数量值时才减去的数量。以下是我的代码。

表格：

<?php
$con = mysql_connect("localhost","root","");
if (!$con)
{
    die('Could not connect: ' . mysql_error());
}

mysql_select_db("dbtest", $con);

$result = mysql_query ("SELECT * FROM recieved_orders");
echo "<table border = '1' style='margin-left:18px;margin-right:18px;' bgcolor='#CFC'>
                <tr>
                    <th bgcolor='#34495E' colspan='9'>
                        <h1><font color='white' align='center'>&nbsp&nbsp&nbspORDER OFFICE SUPPLIES</font></h1>
                    </th>
                </tr>
                <tr bgcolor='#CFC' font size='18'>
                    <th>Item Id</th>
                    <th>Staff Id</th>
                    <th>Quantity</th>
                </tr>";

        while ($row = mysql_fetch_array($result))
        {
            echo "<form action=\"Updateisue.php\" method=\"post\" enctype=\"multipart/form-data\">";
                echo "<tr>";
                    echo "<td><input type=\"text\" name=\"ItemId\"  size=\"30\" value=\" ". $row ['ItemId'] . "\" readonly></td>";
                    echo "<td><input type=\"text\" name=\"StaffId\" value=\" ". $row ['StaffId'] . "\" readonly></td>";
                    echo "<td><input type=\"text\" name=\"Quantity\" value=\" ".$row ['Quantity'] . "\" readonly></td>";
                    echo "<td><input type=\"submit\" name=\"submit\" size=\"30\" style='background-color:#3366FF' value=\"ISSUE  \"></td>";
                echo "</tr>";
            echo "</form>";
        }
echo "</table>";
mysql_close($con);
?>

表单操作：

<?php
include './database-config.php';
$searchError = "";
$searchMessage = "";

function sanitizeString($var) {
    $var = htmlentities($var);
    $var = strip_tags($var);
    $var = stripslashes($var);
    $var = trim($var);
    return $var;
}
$ItemId = sanitizeString($_POST['ItemId']);
$Quantity = sanitizeString($_POST['Quantity']);

if($Quantity<=Quantity){
    $updatePassQuery = "UPDATE stationery SET Quantity=Quantity-$Quantity WHERE ItemId='$ItemId'";
    $executeQuery = mysqli_query($dbh,$updatePassQuery);
if($executeQuery){
    echo " update successful";
    $message  = "update was successful";
    header("location: procurementhome.php");

    } else{
        echo "unsuccessful";
        $error = "update failed";
        // header("location: upstationery.php");
    }
}
else
{
    echo "no more itmes";
}
?>

Answer 1

1） <form>不允许在<table>内。查看form-inside-a-table

2）您必须为所有详细信息保留一个提交按钮。做任何改变并提交。

3）根据第2点，输入的name必须是数组类型。（检查下面的答案）

4）在 Updateisue.php 中，使用for loop或foreach查找每个ItemId并执行查询。

5）在这一行if($Quantity<=Quantity){中。我不知道你从哪里获得Quantity价值。但是，仍然。我假设的是：Quantity针对该特定ItemId。所以，我写了一个查询来执行查找数量。

<?php
$con = mysql_connect("localhost","root","");
if (!$con)
{
    die('Could not connect: ' . mysql_error());
}

mysql_select_db("dbtest", $con);
$result = mysql_query ("SELECT * FROM recieved_orders");

echo "<form action=\"Updateisue.php\" method=\"post\" enctype=\"multipart/form-data\">";
    echo "<table border = '1' style='margin-left:18px;margin-right:18px;' bgcolor='#CFC'>
                    <tr>
                        <th bgcolor='#34495E' colspan='9'>
                            <h1><font color='white' align='center'>&nbsp&nbsp&nbspORDER OFFICE SUPPLIES</font></h1>
                        </th>
                    </tr>
                    <tr bgcolor='#CFC' font size='18'>
                        <th>Item Id</th>
                        <th>Staff Id</th>
                        <th>Quantity</th>
                    </tr>";

            while ($row = mysql_fetch_array($result))
            {
                    echo "<tr>";
                        echo "<td><input type=\"text\" name=\"ItemId[]\"  size=\"30\" value=\" ". $row ['ItemId'] . "\" readonly></td>";
                        echo "<td><input type=\"text\" name=\"StaffId[]\" value=\" ". $row ['StaffId'] . "\" readonly></td>";
                        echo "<td><input type=\"text\" name=\"Quantity[]\" value=\" ".$row ['Quantity'] . "\" readonly></td>";
                        echo "<td><input type=\"submit\" name=\"submit\" size=\"30\" style='background-color:#3366FF' value=\"ISSUE  \"></td>";
                    echo "</tr>";
            }
            echo "<tr><td colspan='3'></td><td><input type=\"submit\" name=\"submit\" size=\"30\" style='background-color:#3366FF' value=\"ISSUE  \"></td></tr>";
    echo "</table>";
echo "</form>";

mysql_close($con);

?>

<强> Updateisue.php

<?php
include './database-config.php';
$searchError = "";
$searchMessage = "";

function sanitizeString($var) {
    $var = htmlentities($var);
    $var = strip_tags($var);
    $var = stripslashes($var);
    $var = trim($var);
    return $var;
}

$totalItem = sizeof($_POST['ItemId']);
$Quantity = $_POST['Quantity'];
for($i=0;$i<$totalItem;$i++) {

    $CItemId = sanitizeString($ItemId[$i]);
    $CQuantity = sanitizeString($Quantity[$i]);

    $quantityAvailable = mysqli_query("SELECT Quantity FROM stationery WHERE ItemId='$CItemId ");
    $row = mysqli_fetch_array($quantityAvailable,MYSQLI_ASSOC); 
    $quantityDB = $row['Quantity'];

    if($CQuantity<=$quantityDB){
        $updatePassQuery = "UPDATE stationery SET Quantity=Quantity-$CQuantity WHERE ItemId='$CItemId'";
        $executeQuery = mysqli_query($dbh,$updatePassQuery);
        if($executeQuery){
            echo " update successful";
            $message  = "update was successful";
            header("location: procurementhome.php");
        } else{
                echo "unsuccessful";
                $error = "update failed";
        }
    }
    else
    {
        echo "no more itmes";
    }
}

?>

仅当字段中的值等于或大于输入值时，如何从MySQL表中的值中减去用户输入值？

1 个答案: