我创建了两个由两个不同数据库表填充的下拉菜单。从菜单中选择了一些东西后,我还创建了一个按钮。我想做的(但我不能)是在屏幕上打印所选项目。在我写的代码之下,直到现在:
<?php
require_once('assets/index.php');
$result1 = $conn->query("select * from partenze");
$result2 = $conn->query("select * from arrivi");
echo "<html>";echo "<body>";echo "<form action='index.php'>"; echo "Select your Departure: <select name='p_id'>";
while ($row1 = $result1->fetch_assoc()) {
unset($pid, $pname);
$pid = $row1['p_id'];
$plocalita = $row1['p_localita'];
echo '<option value="'.$pid.'">'.$plocalita.'</option>';}
echo "</select><br>";echo "Select your Arrival: <select name='a_id'>";
while ($row2 = $result2->fetch_assoc()) {
unset($aid, $aname);
$aid = $row2['a_id'];
$alocalita = $row2['a_localita'];
echo '<option value="'.$aid.'">'.$alocalita.'</option>';}
echo "</select>";
echo "<input type='submit' name='submit' value='Get Selected Values' />"; echo "</form>";
if(isset($_POST['submit'])){
$selected_val1 = $_POST['p_id']; // Storing Selected Value In Variable
$selected_val2 = $_POST['a_id']; // Storing Selected Value In Variable
echo "You have selected :" .$selected_val1. " and " .$selected_val2; // Displaying Selected Value
}
echo "</body>";echo "</html>";
?>
答案 0 :(得分:0)
您正尝试按$_POST
数据检索数据。但在形式上你没有指定请求方法。因此默认情况下需要get
方法。因此,您需要在表单中指定method=post
以从POST
<?php
require_once('assets/index.php');
$result1 = $conn->query("select * from partenze");
$result2 = $conn->query("select * from arrivi");
echo "<html>";
echo "<body>";
echo "<form action='index.php' method='post'>";
echo "Select your Departure:
<select name='p_id'>";
while ($row1 = $result1->fetch_assoc()) {
unset($pid, $pname);
$pid = $row1['p_id'];
$plocalita = $row1['p_localita'];
echo '<option value="'.$pid.'">'.$plocalita.'</option>';}
echo "</select><br>";echo "Select your Arrival: <select name='a_id'>";
while ($row2 = $result2->fetch_assoc()) {
unset($aid, $aname);
$aid = $row2['a_id'];
$alocalita = $row2['a_localita'];
echo '<option value="'.$aid.'">'.$alocalita.'</option>';}
echo "</select>";
echo "<input type='submit' name='submit' value='Get Selected Values' />";
echo "</form>";
if(isset($_POST['submit'])){
$selected_val1 = $_POST['p_id']; // Storing Selected Value In Variable
$selected_val2 = $_POST['a_id']; // Storing Selected Value In Variable
echo "You have selected :" .$selected_val1. " and " .$selected_val2; // Displaying Selected Value
}
echo "</body>";echo "</html>";
?>