<?php $a=array[[]]; $b=array[[]]; if (!empty($a)&&!empty($b)){ echo 1; }else{ echo 2; } ?>
时间: 2024-03-02 10:48:57 浏览: 11
这段 PHP 代码的作用是创建了两个空的二维数组 $a 和 $b,然后判断 $a 和 $b 是否都不为空,如果都不为空则输出 1,否则输出 2。不过这段代码有些问题,因为数组的初始化应该用圆括号而不是方括号,正确的写法应该是:
```
<?php
$a = array();
$b = array();
if (!empty($a) && !empty($b)) {
echo 1;
} else {
echo 2;
}
?>
```
相关问题
找出这串代码的错误并给出正确答案<!DOCTYPE html> <?php $products = array( array("id"=>"1","name"=>"可可芭蕾","price"=>13.00), array("id"=>"2","name"=>"阿华田","price"=>17.00), array("id"=>"3","name"=>"冰淇淋红茶","price"=>8.00), array("id"=>"4","name"=>"百香三重奏","price"=>15.00) ); session_start(); $sum = 0; if(! empty($_SESSION['cart'])) { $order = $_SESSION['cart']; $sum = array_sum(array_column($order, "num")); } ?> <html> <head> <meta charset="UTF-8"> <link rel="stylesheet" type="text/css" href="css/style.css" /> <title>PHP购物</title> </head> <body> <div> <h1>商品列表</h1> <hr> <table> <tr> <th>商品名</th> <th>售价</th> <th>购物车</th> </tr> <?php foreach ($products as $key => $value);?> <tr> <td><?php echo $value['name'];?></td> <td>¥<?php echo $value['price'];?></td> <td><a class="btn" href="addCart.php?upd=add&id=<?php echo $value['id'];?>&name=<?php echo $value['name'];?> &price=<?php echo $value['price'];?>">+</a></td> </tr> <?php endforeach;?> </table> <div> <a href="addCart.php?upd=cart">我的购物车</a> <span><?php echo $sum;?></span> </div> </div> </body> </html>
这段代码的错误是在foreach循环中的分号(;)应该是冒号(:),正确答案如下所示:
<!DOCTYPE html>
<?php
$products = array(
array("id"=>"1","name"=>"可可芭蕾","price"=>13.00),
array("id"=>"2","name"=>"阿华田","price"=>17.00),
array("id"=>"3","name"=>"冰淇淋红茶","price"=>8.00),
array("id"=>"4","name"=>"百香三重奏","price"=>15.00)
);
session_start();
$sum = 0;
if(! empty($_SESSION['cart'])) {
$order = $_SESSION['cart'];
$sum = array_sum(array_column($order, "num"));
}
?>
<html>
<head>
<meta charset="UTF-8">
<link rel="stylesheet" type="text/css" href="css/style.css" />
<title>PHP购物</title>
</head>
<body>
<div>
<h1>商品列表</h1>
<hr>
<table>
<tr>
<th>商品名</th>
<th>售价</th>
<th>购物车</th>
</tr>
<?php foreach ($products as $key => $value): ?>
<tr>
<td><?php echo $value['name'];?></td>
<td>¥<?php echo $value['price'];?></td>
<td><a class="btn" href="addCart.php?upd=add&id=<?php echo $value['id'];?>&name=<?php echo $value['name'];?>&price=<?php echo $value['price'];?>">+</a></td>
</tr>
<?php endforeach; ?>
</table>
<div>
<a href="addCart.php?upd=cart">我的购物车</a>
<span><?php echo $sum;?></span>
</div>
</div>
</body>
</html>
<?php // 连接数据库 $conn = new mysqli("localhost", "root", "123456", "wyya"); // 检查连接是否成功 if ($conn->connect_error) { die("连接失败: " . $conn->connect_error); } // 查询五个歌单的表 $tables = array(); $result = mysqli_query($conn, "SHOW TABLES LIKE '%_list'"); if ($result->num_rows > 0) { while ($row = mysqli_fetch_array($result)) { $tables[] = $row[0]; } } // 获取选中的歌单表 $tableName = isset($_GET["table"]) ? $_GET["table"] : ""; $data = array(); if (!empty($tableName)) { $result = mysqli_query($conn, "SELECT * FROM $tableName"); if ($result->num_rows > 0) { while ($row = $result->fetch_assoc()) { $data[] = $row; } } } ?> <!DOCTYPE html> <html> <head> <title>网易云音乐歌单</title> <style> table { border-collapse: collapse; width: 100%; } th, td { text-align: left; padding: 8px; } tr:nth-child(even) { background-color: #f2f2f2; } th { background-color: #4CAF50; color: white; } .dropdown { position: relative; display: inline-block; } .dropdown-content { display: none; position: absolute; z-index: 1; } .dropdown:hover .dropdown-content { display: block; } </style> </head> <body> <h2>网易云音乐歌单</h2> <div class="dropdown"> <a href="#">分类</a> <div class="dropdown-content"> <?php foreach ($tables as $table) { ?> <a href="?table=<?php echo $table; ?>"><?php echo str_replace("_list", "", $table); ?></a> <?php } ?> </div> </div> <?php if (!empty($tableName)) { ?> <table> <tbody> <tr> <?php $columns = mysqli_query($conn, "SHOW COLUMNS FROM $tableName"); if ($columns->num_rows > 0) { while ($column = mysqli_fetch_array($columns)) { ?> <th><?php echo $column["Field"]; ?></th> <?php } } ?> </tr> <?php foreach ($data as $row) { ?> <tr> <?php foreach ($row as $value) { ?> <td><?php echo $value; ?></td> <?php } ?> </tr> <?php } ?> </tbody> </table> <?php } ?> </body> </html> <?php // 关闭连接 $conn->close(); ?>修改代码,将one修改成华语,two修改成欧美,three修改成日语,four修改成韩语,five修改成粤语
可以将以下代码:
<?php foreach ($tables as $table) { ?>
<a href="?table=<?php echo $table; ?>"><?php echo str_replace("_list", "", $table); ?></a>
<?php } ?>
修改为:
<?php
$language = array(
"one" => "华语",
"two" => "欧美",
"three" => "日语",
"four" => "韩语",
"five" => "粤语",
);
foreach ($tables as $table) {
$tableName = str_replace("_list", "", $table);
$languageKey = array_search($tableName, $language);
?>
<a href="?table=<?php echo $table; ?>"><?php echo $language[$languageKey]; ?></a>
<?php } ?>