我目前有一个数据库，其中包含学生选择的运动选项。我有一个名为 StudentChoices.php 的页面，允许学生选择他们的运动选项。如果数据库中存在包含其用户 ID 的记录，我将如何使用其运动选项填充页面中的下拉列表、禁用它们并隐藏提交按钮？
<body>
<div class='container col-md-8 rounded p-5 mt-5 border'>
<h2 class='text-center'>Oundle School Sports Database</h2>
<h4 class='pt-4'><?php echo 'Welcome: '.$_SESSION['name'] ?></h4>
<h5 class='pt-2'>Please fill all forms</h5>
<form action="postChoice.php" method ="post">
<div class='py-2 row'>
<div class='col-md-4'>
<select name="term1sport" class='custom-select'>
<option value=" " selected disabled>Please select a first term sport...</option>
<?php
include_once('connection.php');
try{
$stmt = $conn->prepare(
"SELECT DISTINCT c.Choice_ID, s.Name
From Sports AS s INNER JOIN Choices As c
ON c.Sport_ID = s.Sport_ID INNER JOIN Year As y
ON y.Year_ID = c.Year_ID
Where y.Code Like CONCAT('%', :year, '%') AND
c.Current = 'Y' AND
c.Sex IN (:sex, 'B') AND
c.Term_ID = 1 ORDER BY Name ASC");
$stmt->bindParam(':year', $_SESSION['year']);
$stmt->bindParam(':sex', $_SESSION['sex']);
$stmt->execute();
while ($row = $stmt->fetch(PDO::FETCH_ASSOC))
{
echo("<option value='".$row['Choice_ID']."'>".$row['Name']."</option>");
}
}
catch(PDOException $e)
{
echo "error".$e->getMessage();
}
?>
</select>
</div>
<div class='col-md-4'>
<select name="term2sport" class='custom-select'>
<option value=" " selected disabled>Please select a second term sport...</option>
<?php
include_once('connection.php');
try{
$stmt = $conn->prepare(
"SELECT DISTINCT c.Choice_ID, s.Name
From Sports AS s INNER JOIN Choices AS c
ON c.Sport_ID = s.Sport_ID INNER JOIN Year AS y
ON y.Year_ID = c.Year_ID
Where y.Code Like CONCAT('%', :year, '%') AND
c.Current = 'Y' AND
c.Sex IN (:sex, 'B') AND
c.Term_ID = 2 ORDER BY Name ASC");
$stmt->bindParam(':year', $_SESSION['year']);
$stmt->bindParam(':sex', $_SESSION['sex']);
$stmt->execute();
while ($row = $stmt->fetch(PDO::FETCH_ASSOC))
{
echo("<option value='".$row['Choice_ID']."'>".$row['Name']."</option>");
}
}
catch(PDOException $e)
{
echo "error".$e->getMessage();
}
?>
</select>
</div>
<div class='col-md-4'>
<select name="term3sport" class='custom-select'>
<option value=" " selected disabled>Please select a third term sport...</option>
<?php
include_once('connection.php');
try{
$stmt = $conn->prepare(
"SELECT DISTINCT c.Choice_ID, s.Name
From Sports AS s INNER JOIN Choices As c
ON c.Sport_ID = s.Sport_ID INNER JOIN Year As y
ON y.Year_ID = c.Year_ID
Where y.Code Like CONCAT('%', :year, '%') AND
c.Current = 'Y' AND
c.Sex IN (:sex, 'B') AND
c.Term_ID = 3 ORDER BY Name ASC");
$stmt->bindParam(':year', $_SESSION['year']);
$stmt->bindParam(':sex', $_SESSION['sex']);
$stmt->execute();
while ($row = $stmt->fetch(PDO::FETCH_ASSOC))
{
echo("<option value='".$row['Choice_ID']."'>".$row['Name']."</option>");
}
}
catch(PDOException $e)
{
echo "error".$e->getMessage();
}
?>
</select>
</div>
</div>
<div class='py-2 row'>
<div class='col-md-12'>
<input class='btn btn-success float-right'type="submit" value="Submit Choices">
</div>
</div>
</form>
最佳答案
使用评论的帮助，我在数据库中查找了用户并计算了记录数。如果数字大于 1，我就会在下拉列表中查找该运动的值。然后我使用 javascript 更新了它们并禁用了它们。可能不是最好的代码，但它可以工作。
<?php
ini_set('display_errors', 1);
ini_set('display_startup_errors', 1);
error_reporting(E_ALL);
include_once('connection.php');
if($_SERVER['REQUEST_METHOD'] == "POST" and isset($_POST['someAction']))
{
func();
}
function func()
{
$conn = mysqli_connect("localhost", "root", "", "SportsDB");
}
session_start();
if( !isset($_SESSION['username']) ){
header('Location:login.php');
}
print_r($_SESSION);
?>
<!DOCTYPE html>
<html>
<title>Choices</title>
<!--- Link to CDN for Bootstrap 4, jQuery and DataTables -->
<link rel="stylesheet" type="text/css" href="https://cdn.datatables.net/v/bs4-4.1.1/jq-3.3.1/jszip-2.5.0/dt-1.10.18/af-2.3.2/b-1.5.4/b-colvis-1.5.4/b-flash-1.5.4/b-html5-1.5.4/b-print-1.5.4/cr-1.5.0/fc-3.2.5/fh-3.1.4/kt-2.5.0/r-2.2.2/rg-1.1.0/rr-1.2.4/sc-1.5.0/sl-1.2.6/datatables.min.css"
/>
<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/pdfmake/0.1.36/pdfmake.min.js"></script>
<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/pdfmake/0.1.36/vfs_fonts.js"></script>
<script type="text/javascript" src="https://cdn.datatables.net/v/bs4-4.1.1/jq-3.3.1/jszip-2.5.0/dt-1.10.18/af-2.3.2/b-1.5.4/b-colvis-1.5.4/b-flash-1.5.4/b-html5-1.5.4/b-print-1.5.4/cr-1.5.0/fc-3.2.5/fh-3.1.4/kt-2.5.0/r-2.2.2/rg-1.1.0/rr-1.2.4/sc-1.5.0/sl-1.2.6/datatables.min.js"></script>
<link rel="stylesheet" type="text/css" href="css/stylesheet.css" />
<body>
<div class='container col-md-8 rounded p-5 mt-5 border'>
<h2 class='text-center'>Oundle School Sports Database</h2>
<h4 class='pt-4'>
<?php echo 'Welcome: '.$_SESSION['name'] ?>
</h4>
<h5 class='pt-2'>Please fill all forms</h5>
<form action="postChoice.php" method="post">
<div class='py-2 row'>
<div class='col-md-4'>
<select name="term1sport" id='select1' class='custom-select'>
<option value=" " selected disabled>Please select a first term sport...</option>
<?php
try{
$stmt = $conn->prepare(
"SELECT DISTINCT c.Choice_ID, s.Name
From Sports AS s INNER JOIN Choices As c
ON c.Sport_ID = s.Sport_ID INNER JOIN Year As y
ON y.Year_ID = c.Year_ID
Where y.Code Like CONCAT('%', :year, '%') AND
c.Current = 'Y' AND
c.Sex IN (:sex, 'B') AND
c.Term_ID = 1 ORDER BY Name ASC");
$stmt->bindParam(':year', $_SESSION['year']);
$stmt->bindParam(':sex', $_SESSION['sex']);
$stmt->execute();
while ($row = $stmt->fetch(PDO::FETCH_ASSOC))
{
echo("
<option value='".$row['Choice_ID']."'>".$row['Name']."</option>");
}
}
catch(PDOException $e)
{
echo "error".$e->getMessage();
}
?>
</select>
</div>
<div class='col-md-4'>
<select name="term2sport" id='select2' class='custom-select'>
<option value=" " selected disabled>Please select a second term sport...</option>
<?php
try{
$stmt = $conn->prepare(
"SELECT DISTINCT c.Choice_ID, s.Name
From Sports AS s INNER JOIN Choices AS c
ON c.Sport_ID = s.Sport_ID INNER JOIN Year AS y
ON y.Year_ID = c.Year_ID
Where y.Code Like CONCAT('%', :year, '%') AND
c.Current = 'Y' AND
c.Sex IN (:sex, 'B') AND
c.Term_ID = 2 ORDER BY Name ASC");
$stmt->bindParam(':year', $_SESSION['year']);
$stmt->bindParam(':sex', $_SESSION['sex']);
$stmt->execute();
while ($row = $stmt->fetch(PDO::FETCH_ASSOC))
{
echo("
<option value='".$row['Choice_ID']."'>".$row['Name']."</option>");
}
}
catch(PDOException $e)
{
echo "error".$e->getMessage();
}
?>
</select>
</div>
<div class='col-md-4'>
<select name="term3sport" id='select3' class='custom-select'>
<option value=" " selected disabled>Please select a third term sport...</option>
<?php
try{
$stmt = $conn->prepare(
"SELECT DISTINCT c.Choice_ID, s.Name
From Sports AS s INNER JOIN Choices As c
ON c.Sport_ID = s.Sport_ID INNER JOIN Year As y
ON y.Year_ID = c.Year_ID
Where y.Code Like CONCAT('%', :year, '%') AND
c.Current = 'Y' AND
c.Sex IN (:sex, 'B') AND
c.Term_ID = 3 ORDER BY Name ASC");
$stmt->bindParam(':year', $_SESSION['year']);
$stmt->bindParam(':sex', $_SESSION['sex']);
$stmt->execute();
while ($row = $stmt->fetch(PDO::FETCH_ASSOC))
{
echo("
<option value='".$row['Choice_ID']."'>".$row['Name']."</option>");
}
}
catch(PDOException $e)
{
echo "error".$e->getMessage();
}
?>
</select>
</div>
</div>
<div class='py-2 row'>
<div class='col-md-12'>
<input class='btn btn-success float-right' type="submit" value="Submit Choices">
</div>
</div>
</form>
<div class="collapse" id='testid'>
<h6>Success</h6>
</div>
<div>
<!-- Circus T1 code -->
</div>
<div>
<!-- Circus T2 code -->
</div>
<div>
<!-- Circus T3 code -->
</div>
<div>
<!-- Rules and stuff go here -->
</div>
<form action="process.php" method="post" class='col-md-12'>
<div class="text-center col-md-12">
<input type="submit" class="btn btn-primary btn-sx" value="Logout">
</div>
</form>
</div>
<?php
$stmt=$conn->prepare('SELECT COUNT(1) FROM Student_Choices JOIN Current_DB ON DB_Year = DB WHERE Username = :username');
$stmt->bindParam(':username', $_SESSION['username']);
$stmt->execute();
$row=$stmt->fetch(PDO::FETCH_ASSOC);
{
//Now to check, we use an if() statement
if($row['COUNT(1)'] >= 1) {
$stmt = $conn->prepare(
"SELECT st.Name AS student, st.House AS house,
(CASE WHEN st.Year = 6 THEN 'L6' WHEN st.Year = 7 THEN 'U6' ELSE st.Year END) as year,
c1.Choice_ID AS T1, c2.Choice_ID AS T2, c3.Choice_ID AS T3
From Students AS st
INNER JOIN Student_Choices AS sc
ON st.Username = sc.Username INNER JOIN Current_DB AS db
ON sc.DB_year = db.DB
INNER JOIN Choices AS c1
ON sc.T1_Choice = c1.Choice_ID
INNER JOIN Sports AS T1
ON c1.Sport_ID = T1.Sport_ID
INNER JOIN Choices AS c2
ON sc.T2_Choice = c2.Choice_ID
INNER JOIN Sports AS T2
ON c2.Sport_ID = T2.Sport_ID
INNER JOIN Choices AS c3
ON sc.T3_Choice = c3.Choice_ID
INNER JOIN Sports AS T3
ON c3.Sport_ID = T3.Sport_ID
Where sc.Username = :username
");
$stmt->bindParam(':username', $_SESSION['username']);
$stmt->execute();
while ($row = $stmt->fetch(PDO::FETCH_ASSOC)) {
echo '
<script>';
echo 'document.getElementById("select1").value='.$row['T1'].';';
echo 'document.getElementById("select1").disabled=true;';
echo 'document.getElementById("select2").value='.$row['T2'].';';
echo 'document.getElementById("select2").disabled=true;';
echo 'document.getElementById("select3").value='.$row['T3'].';';
echo 'document.getElementById("select3").disabled=true;';
echo '</script>';
}
}
}
?>
</body>
</html>关于php - 如果数据库中存在记录，则填充并锁定下拉列表，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/53320339/