Question

现在，如果我使用获取变量one和two加载页面，它将重定向，但它会显示此错误：Warning: Cannot modify header information - headers already sent by (output started at /home/site/public_html/lp-19.php:3) in /home/site/public_html/lp-19.php on line 5

继承我的代码：

<?php if(isset($_GET['one']) && isset($_GET['two'])) {?>

<?php
$value = "none";
setcookie("Disagree", $value, time()+30);
?>


<!DOCTYPE html>
<html>
<head>
<script type='text/javascript' src='//redirect.com/script.js'></script>
</head>
<body>
set "Disagree" cookie and then redirect
</body>
</html>

<?php } else { ?>

<?php
$value = "agree";
setcookie("Yes", $value, time()+3000000);
?>

<!DOCTYPE html>
<html>
set "yes" cookie and display content if no "one" or "two" get variables in url
</html>
<?php }?>

如何摆脱错误并让php根据加载的页面设置cookie？

Answer 1

问题是因为cookie在响应头中发送，必须在响应主体之前发送到浏览器。输出任何内容都会进入响应主体。

您可以通过多种方式解决此问题，包括输出缓冲，或者只是运行所有逻辑，这些逻辑将在输出代码之前输出标头，但是在这里，您似乎只输出数据来执行javascript重定向。

不要加载javascript只是为了重定向，在php中设置一个重定向头，它还简化了你的代码：

<?php 
if(isset($_GET['one']) && isset($_GET['two'])) {
    $value = "none";
    setcookie("Disagree", $value, time()+30);
    header('Location: redirectUrlHere'); //<-set the correct url
    die();
}
$value = "agree";
setcookie("Yes", $value, time()+3000000);
?>

<!DOCTYPE html>
<html>
   ...
</html>

根据您的评论编辑：

<?php 
if(isset($_GET['one']) && isset($_GET['two'])) {
    $value = "none";
    setcookie("Disagree", $value, time()+30);
}else{
    $value = "agree";
     setcookie("Yes", $value, time()+3000000);
}

if($value=="none"):?>
    <!DOCTYPE html>
    <html>
        <head>
           <script type='text/javascript' src='//redirect.com/script.js'></script>
        </head>
        <body></body>
    </html>
<?php else:?>
    <!DOCTYPE html>
    <html>
        ...
    </html>
<?php endif;?>

Answer 2

试试这个;）

<?php
$has_value = isset($_GET['one']) && isset($_GET['two']);

if(!$has_value) {
    $value = "agree";
    setcookie("Yes", $value, time() + 3000000);
}

if($has_value) {
    $value = "none";
    setcookie("Disagree", $value, time() + 30);
    ?>
    <!DOCTYPE html>
    <html>
    <head>
        <script type='text/javascript' src='//redirect.com/script.js'></script>
    </head>
    <body>
    set "Disagree" cookie and then redirect
    </body>
    </html>

<?php
}
else {
    ?>

    <!DOCTYPE html>
    <html>
    set "yes" cookie and display content if no "one" or "two" get variables in url
    </html>
<?php }

标题已发送

2 个答案: