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Correction status：qualified
Teacher's comments：代码不仅要写正确, 还要记住
Collection
Collection
PHP知识：
1. <?php ?>
2. 创建变量直接： $value = value； 数组 $arr = ['……','……','……']；
3. foreach() 遍历 例： foreach( $movies as $key => $value){……};
<?php $title = '这是标题'; ?>
<?php $array = ['内容1','内容2','内容3'] ;?>
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title> <?php echo $title; ?> </title>
</head>
<body>
<h2><?php echo $title; ?></h2>
<!--foreach() foreach遍历输出html内容-->
<?php foreach ($array as $key => $value){ ?>
<li><a href="#"> <?php echo $value; ?></a></li>
<?php } ?>
<hr>
<!--foreach()替代语法输出html内容-->
<?php foreach ($array as $array): ?>
<li><a href=""><?php echo $array; ?></a></li>
<?php endforeach; ?>
</body>
</html>点击 "运行实例" 按钮查看在线实例
GET/POST处理：
1. echo '<pre>' 格式化输出；
2. print_r ($_GET) ; 打印GET；
3. 获取变量之前用isset()进行判断
if (isset($_GET['email'])) {
echo $_GET['email']; //GET改为POST
} else { // 给个默认值
$_GET['email'] = ''; //GET改为POST
}简化 三元运算符
echo isset($_GET['email']) ? $_GET['email'] : '' ; //GET改为POST
粘性表单：
<input type="text" name="name名" id="id名" value="<?php echo isset($_GET['email']) ? $_GET['email'] : '' ; ?>"
<?php $title = '这是表单'; ?>
<?php $array = ['内容1','内容2','内容3'] ;?>
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title> <?php echo $title; ?> </title>
</head>
<body>
<form action="" method="get">
<label for="username">账号：</label>
<input type="text" name="username" id="username" value="echo isset($_GET['username']) ? $_GET['username'] : ''">
<br>
<label for="pwd">密码：</label>
<input type="password" name="pwd" id="pwd" value="echo isset($_GET['pwd']) ? $_GET['pwd'] : ''">
<br>
<label for="email">邮箱：</label>
<input type="email" name="email" id="email" value="echo isset($_GET['email']) ? $_GET['email'] : '';">
<br>
<button>登录</button>
<?php
echo '<pre>';
print_r($_GET);
// if (isset($_GET['email'])){
// echo $_GET['email'];
// }else{
// $_GET['email'] = '';
// }
?>
</form>
</body>
</html>点击 "运行实例" 按钮查看在线实例
<?php $title = '这是表单'; ?> <?php $array = ['内容1','内容2','内容3'] ;?> <!doctype html> <html lang="en"> <head> <meta charset="UTF-8"> <title> <?php echo $title; ?> </title> </head> <body> <form action="" method="post"> <label for="username">账号：</label> <input type="text" name="username" id="username" value="<?php echo isset($_POST['username']) ? $_POST['username'] : ''; ?>"> <br> <label for="pwd">密码：</label> <input type="password" name="pwd" id="pwd" value="<?php echo isset($_POST['pwd']) ? $_POST['pwd'] : '';?>"> <br> <label for="email">邮箱：</label> <input type="email" name="email" id="email" value="<?php echo isset($_POST['email']) ? $_POST['email'] : '';?>"> <br> <button>登录</button> <?php echo '<pre>'; print_r($_POST); ?> </form> </body> </html>
点击 "运行实例" 按钮查看在线实例