Cannot modify header information headr函数问题,代码很简单
login.php
<br />
<html><br />
<title><br />
登陆界面<br />
</title><br />
<head><br />
<meta http-equiv="content-type" content="text/html;charset=utf-8" /><br />
</head><br />
<body><br />
<form action="loginController.php" method="post"><br />
<table><br />
<tr><td>用户名:</td><td><input type="text" name="username"/></td></tr><br />
<tr><td>密码:</td><td><input type="text" name="password"/></td></tr><br />
<tr><td><input type="submit" value="登陆"/><td><input type="reset" name="重新填写"/></td></tr><br />
</table><br />
</form><br />
</body><br />
</html><br />
<br />
loginController.php<br />
<html><br />
<title><br />
验证控制器<br />
</title><br />
<head><br />
<meta http-equiv="content-type" content="text/html;charset=utf-8" /><br />
</head><br />
<body><br />
<?php<br />
$username=$_REQUEST['username'];<br />
$password=$_REQUEST['password'];<br />
if($username=='123'&&$password=='123'){<br />
header("location:Manage.php");<br />
exit();<br />
} else{<br />
echo '账号密码有误';<br />
}<br />
?><br />
</body><br />
</html><br />
<br />
<html><br />
<title><br />
管理界面<br />
</title><br />
<head><br />
<meta http-equiv="content-type" content="text/html;charset=utf-8" /><br />
</head><br />
<body><br />
<h1 id="欢迎管理员">欢迎管理员</h1><br />
</body><br />
</html><br />
<br />
输入用户名密码123<br />
错误提示如下：<br />
Warning: Cannot modify header information - headers already sent by (output started at C:\wamp\www\sqlInjcetion\loginController.php:9) in C:\wamp\www\sqlInjcetion\loginController.php on line 13<br />
<br />
求解！<br />
另外3个php文件都是utf-8编码<br />
------解决方案--------------------
------解决方案--------------------
你那么多html代码就是输出了
搜索下php缓冲区 header
这个问题的解释还是很多的呀.............
header("location:manage.php")
也可以换成
eacho "<script>window.location.href='manage.php'</script>";
------解决方案--------------------
根据http原理（注意跟php没啥关系）
http头必须先于http实体输出
所以
从你的.php文件输出了第一个非 此时再输出http响应头则无济于事，werbserver也做不了这个事情了。
------解决方案--------------------
补充一句，header本身就是修改http响应头，重定向location:只是一种的一种用法（实际被加上了302响应码）
------解决方案--------------------
注意文件格式。bom头
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