我使用的是以下代码：
<!DOCTYPE html>
<html>
<head>
<title>TechBuzz-Incredible Saurav</title>
<meta charset="utf-8">
<link href="css/style.css" rel='stylesheet' type='text/css' />
<meta name="viewport" content="width=device-width, initial-scale=1">
</head>
<?php
session_start();
if (ISSET($_GET['login'])) {
if ($_POST ['password'] == 'iamgreat' ) {
$_SESSION['loggedin'] = 1;
header("Location:redirect.php");
exit;
}
else echo "Wrong details" ;
}
?>
<body bgcolor="black">
<!-----start-main---->
<div class="login-form">
<div class="head">
<img src="images/mem2.jpg" alt=""/>
</div>
<form action= "?login=1" method="post">
<font face="comic sans ms" color=grey size="5px"> <b> Please Login to TechBuzz: </b> </font><br><br>
<li>
<input type="password" name="password""><a href="#" class=" icon lock" /></a>
</li>
<div class="p-container">
<label class="checkbox"><input type="checkbox" name="checkbox" checked><i></i>Remember Me</label>
<input type="submit" />
<div class="clear"> </div>
</div>
</form>
</div>
</body>
</html>
当我运行此程序并输入错误的密码时，页面顶部会显示"错误的详细信息"。我想改变这个else echo "Wrong details";的位置。有人能帮我吗？我是个初学者。
如何设置2个密码？
这确实是一项非常简单的任务。你所需要做的就是设置一个变量，并在下面回显它。
在任何需要回显错误的位置使用<?php echo $error; ?>。else语句将值设置为$error；否则，它是一个空白字符串，因此即使在被呼应时也不会显示任何内容。
此外，您应该将php移到页面的顶部。这是完整的代码：
<?php
session_start();
$error = ""; // set blank string to start with
if (isset($_GET['login'])) {
if ($_POST['password'] == 'iamgreat') {
$_SESSION['loggedin'] = 1;
header("Location:redirect.php");
exit;
}
else $error = "<div style='color: red;'>Wrong Details</div>";
}
?>
<!DOCTYPE html>
<html>
<head>
<title>TechBuzz-Incredible Saurav</title>
<meta charset="utf-8">
<link href="css/style.css" rel='stylesheet' type='text/css' />
<meta name="viewport" content="width=device-width, initial-scale=1">
</head>
<body bgcolor="black">
<!-----start-main---->
<div class="login-form">
<div class="head">
<img src="images/mem2.jpg" alt=""/>
</div>
<form action= "?login=1" method="post">
<font face="comic sans ms" color=grey size="5px"> <b> Please Login to TechBuzz: </b> </font><br><br>
<?php echo $error; ?>
<li>
<input type="password" name="password" onfocus="this.value = '';" onblur="if (this.value == '') {this.value = 'Password';}"><a href="#" class=" icon lock" /></a>
</li>
<div class="p-container">
<label class="checkbox"><input type="checkbox" name="checkbox" checked><i></i>Remember Me</label>
<input type="submit" />
<div class="clear"> </div>
</div>
</form>
</div>
</body>
</html>
正如您的评论所示，您需要在页面底部显示该错误。我在提交按钮之前添加那个错误&密码后字段。这样用户就可以很容易地看到按钮附近的错误。
<!DOCTYPE html>
<html>
<head>
<title>TechBuzz-Incredible Saurav</title>
<meta charset="utf-8">
<link href="css/style.css" rel='stylesheet' type='text/css' />
<meta name="viewport" content="width=device-width, initial-scale=1">
</head>
<?php
session_start();
if (ISSET($_GET['login'])) {
if ($_POST ['password'] == 'iamgreat' ) {
$_SESSION['loggedin'] = 1;
header("Location:redirect.php");
exit;
}
else $msg="Wrong details" ;
}
?>
<body bgcolor="black">
<!-----start-main---->
<div class="login-form">
<div class="head">
<img src="images/mem2.jpg" alt=""/>
</div>
<form action= "?login=1" method="post">
<font face="comic sans ms" color=grey size="5px"> <b> Please Login to TechBuzz: </b> </font><br><br>
<li>
<input type="password" name="password""><a href="#" class=" icon lock" /></a>
</li><br /> <font size="3" color="red"><?php echo $msg; ?></font>
<div class="p-container">
<label class="checkbox"><input type="checkbox" name="checkbox" checked><i></i>Remember Me</label>
<input type="submit" />
<div class="clear"> </div>
</div>
</form>
</div>
</body>
</html>
正如我在评论中提到的。将header()等向上移动到顶部，然后设置一个变量，如$error。稍后在页面和echo上检查您想要的位置：
<?php
session_start();
if(isset($_GET['login'])) {
if($_POST['password'] == 'iamgreat' ) {
$_SESSION['loggedin'] = 1;
header("Location:redirect.php");
exit;
}
// You don't really need an else here
// seeings as it will either exit or error
$error = true;
} ?><!DOCTYPE html>
<html>
<head>
<title>TechBuzz-Incredible Saurav</title>
<meta charset="utf-8">
<link href="css/style.css" rel='stylesheet' type='text/css' />
<meta name="viewport" content="width=device-width, initial-scale=1">
</head>
<body bgcolor="black">
<!-----start-main---->
<div class="login-form">
<div class="head">
<img src="images/mem2.jpg" alt=""/>
</div>
<!-- Here you can either echo the text, or show a block of html:
Option 1
<?php if(isset($error)) echo "Wrong details"; ?>
-->
<!-- Option 2 -->
<?php if(isset($error)) { ?>
<h2>Wrong details</h2><?php } ?>
<form action="?login=1" method="post">
<font face="comic sans ms" color=grey size="5px"><b>Please Login to TechBuzz: </b></font><br><br>
<!-- You have no <ul> or <ol> -->
<li><input type="password" name="password""><a href="#" class=" icon lock" /></a></li>
<div class="p-container">
<label class="checkbox"><input type="checkbox" name="checkbox" checked><i></i>Remember Me</label>
<input type="submit" />
<div class="clear"></div>
</div>
</form>
</div>
</body>
</html>
在下面的答案中，我将向您展示一种简单的javascript方法，但如果您使用JQUERY，那么处理这样的事情就非常简单了------学习JQUERY，它将帮助您进行高级web开发。
<!DOCTYPE html>
<html>
<head>
<title>TechBuzz-Incredible Saurav</title>
<meta charset="utf-8">
<link href="css/style.css" rel='stylesheet' type='text/css' />
<meta name="viewport" content="width=device-width, initial-scale=1">
<?php
session_start();
if (ISSET($_GET['login'])) {
if ($_POST ['password'] == 'iamgreat' ) {
$_SESSION['loggedin'] = 1;
header("Location:redirect.php");
exit;
}
else echo "<script>document.getElementById("errorMsg").style.display = "visible";</script>" ;
}
?>
</head>
<body bgcolor="black">
<!-----start-main---->
<div class="login-form">
<div class="head">
<img src="images/mem2.jpg" alt=""/>
</div>
<!-----Put this DIV where you want to show message---->
<div id="errorMsg" style="display:none">Wrong Details</div>
<form action= "?login=1" method="post">
<font face="comic sans ms" color=grey size="5px"> <b> Please Login to TechBuzz: </b> </font><br><br>
<li>
<input type="password" name="password" onfocus="this.value = '';" onblur="if (this.value == '') {this.value = 'Password';}"><a href="#" class=" icon lock" /></a>
</li>
<div class="p-container">
<label class="checkbox"><input type="checkbox" name="checkbox" checked><i></i>Remember Me</label>
<input type="submit" />
<div class="clear"> </div>
</div>
</form>
</div>
</body>
</html>