我用dreamweaver CS4 做的一个PHP登录界面。但是运行登录界面的时候提示出错,我在网上找了一下,没有找到解决的方案,希望出过类似问题的朋友能够指点一下。错误提示:
Warning: session_start() [function.session-start]: Cannot send session cookie - headers already sent by (output started at C:\xampp\htdocs\jiajia\login.php:1) in C:\xampp\htdocs\jiajia\login.php on line 0Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at C:\xampp\htdocs\jiajia\login.php:1) in C:\xampp\htdocs\jiajia\login.php on line 0Warning: Cannot modify header information - headers already sent by (output started at C:\xampp\htdocs\jiajia\login.php:1) in C:\xampp\htdocs\jiajia\login.php on line 73
代码如下:
<?php virtual('/jiajia/Connections/conn.php'); ?>
<?php
if (!function_exists("GetSQLValueString")) {
function GetSQLValueString($theValue, $theType, $theDefinedValue = "", $theNotDefinedValue = "")
{
if (PHP_VERSION < 6) {
$theValue = get_magic_quotes_gpc() ? stripslashes($theValue) : $theValue;
} $theValue = function_exists("mysql_real_escape_string") ? mysql_real_escape_string($theValue) : mysql_escape_string($theValue); switch ($theType) {
case "text":
$theValue = ($theValue != "") ? "'" . $theValue . "'" : "NULL";
break;
case "long":
case "int":
$theValue = ($theValue != "") ? intval($theValue) : "NULL";
break;
case "double":
$theValue = ($theValue != "") ? doubleval($theValue) : "NULL";
break;
case "date":
$theValue = ($theValue != "") ? "'" . $theValue . "'" : "NULL";
break;
case "defined":
$theValue = ($theValue != "") ? $theDefinedValue : $theNotDefinedValue;
break;
}
return $theValue;
}
}
?>
<?php
// *** Validate request to login to this site.
if (!isset($_SESSION)) {
session_start();
}$loginFormAction = $_SERVER['PHP_SELF'];
if (isset($_GET['accesscheck'])) {
$_SESSION['PrevUrl'] = $_GET['accesscheck'];
}if (isset($_POST['username'])) {
$loginUsername=$_POST['username'];
$password=$_POST['password'];
$MM_fldUserAuthorization = "level";
$MM_redirectLoginSuccess = "checkmsg.php";
$MM_redirectLoginFailed = "login.php";
$MM_redirecttoReferrer = false;
mysql_select_db($database_conn, $conn);
$LoginRS__query=sprintf("SELECT username, password, level FROM member WHERE username=%s AND password=%s",
GetSQLValueString($loginUsername, "text"), GetSQLValueString($password, "text"));
$LoginRS = mysql_query($LoginRS__query, $conn) or die(mysql_error());
$loginFoundUser = mysql_num_rows($LoginRS);
if ($loginFoundUser) {
$loginStrGroup = mysql_result($LoginRS,0,'level');
//declare two session variables and assign them
$_SESSION['MM_Username'] = $loginUsername;
$_SESSION['MM_UserGroup'] = $loginStrGroup; if (isset($_SESSION['PrevUrl']) && false) {
$MM_redirectLoginSuccess = $_SESSION['PrevUrl'];
}
header("Location: " . $MM_redirectLoginSuccess );
}
else {
header("Location: ". $MM_redirectLoginFailed );
}
}
?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<style type="text/css">
<!--
.dd {
font-size: 36px;
}
-->
</style>
</head><body>
<p> </p>
<p> </p>
<table width="992" height="236" border="1">
<tr>
<td height="230">
<p class="dd"> 请先登录 </p>
<form id="form2" name="form2" method="POST" action="<?php echo $loginFormAction; ?>">
<p> 账号:
<input type="text" name="username" id="username" />
</p>
<p> 密码:
<input type="text" name="password" id="password" />
</p>
<p>
<input type="submit" name="button" id="button" value="登录" />
</p>
<p> </p>
</form></td>
</tr>
</table>
</body>
</html>
Warning: session_start() [function.session-start]: Cannot send session cookie - headers already sent by (output started at C:\xampp\htdocs\jiajia\login.php:1) in C:\xampp\htdocs\jiajia\login.php on line 0Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at C:\xampp\htdocs\jiajia\login.php:1) in C:\xampp\htdocs\jiajia\login.php on line 0Warning: Cannot modify header information - headers already sent by (output started at C:\xampp\htdocs\jiajia\login.php:1) in C:\xampp\htdocs\jiajia\login.php on line 73
代码如下:
<?php virtual('/jiajia/Connections/conn.php'); ?>
<?php
if (!function_exists("GetSQLValueString")) {
function GetSQLValueString($theValue, $theType, $theDefinedValue = "", $theNotDefinedValue = "")
{
if (PHP_VERSION < 6) {
$theValue = get_magic_quotes_gpc() ? stripslashes($theValue) : $theValue;
} $theValue = function_exists("mysql_real_escape_string") ? mysql_real_escape_string($theValue) : mysql_escape_string($theValue); switch ($theType) {
case "text":
$theValue = ($theValue != "") ? "'" . $theValue . "'" : "NULL";
break;
case "long":
case "int":
$theValue = ($theValue != "") ? intval($theValue) : "NULL";
break;
case "double":
$theValue = ($theValue != "") ? doubleval($theValue) : "NULL";
break;
case "date":
$theValue = ($theValue != "") ? "'" . $theValue . "'" : "NULL";
break;
case "defined":
$theValue = ($theValue != "") ? $theDefinedValue : $theNotDefinedValue;
break;
}
return $theValue;
}
}
?>
<?php
// *** Validate request to login to this site.
if (!isset($_SESSION)) {
session_start();
}$loginFormAction = $_SERVER['PHP_SELF'];
if (isset($_GET['accesscheck'])) {
$_SESSION['PrevUrl'] = $_GET['accesscheck'];
}if (isset($_POST['username'])) {
$loginUsername=$_POST['username'];
$password=$_POST['password'];
$MM_fldUserAuthorization = "level";
$MM_redirectLoginSuccess = "checkmsg.php";
$MM_redirectLoginFailed = "login.php";
$MM_redirecttoReferrer = false;
mysql_select_db($database_conn, $conn);
$LoginRS__query=sprintf("SELECT username, password, level FROM member WHERE username=%s AND password=%s",
GetSQLValueString($loginUsername, "text"), GetSQLValueString($password, "text"));
$LoginRS = mysql_query($LoginRS__query, $conn) or die(mysql_error());
$loginFoundUser = mysql_num_rows($LoginRS);
if ($loginFoundUser) {
$loginStrGroup = mysql_result($LoginRS,0,'level');
//declare two session variables and assign them
$_SESSION['MM_Username'] = $loginUsername;
$_SESSION['MM_UserGroup'] = $loginStrGroup; if (isset($_SESSION['PrevUrl']) && false) {
$MM_redirectLoginSuccess = $_SESSION['PrevUrl'];
}
header("Location: " . $MM_redirectLoginSuccess );
}
else {
header("Location: ". $MM_redirectLoginFailed );
}
}
?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<style type="text/css">
<!--
.dd {
font-size: 36px;
}
-->
</style>
</head><body>
<p> </p>
<p> </p>
<table width="992" height="236" border="1">
<tr>
<td height="230">
<p class="dd"> 请先登录 </p>
<form id="form2" name="form2" method="POST" action="<?php echo $loginFormAction; ?>">
<p> 账号:
<input type="text" name="username" id="username" />
</p>
<p> 密码:
<input type="text" name="password" id="password" />
</p>
<p>
<input type="submit" name="button" id="button" value="登录" />
</p>
<p> </p>
</form></td>
</tr>
</table>
</body>
</html>
session_start();
//保证在第一行
?>
<html>
<head>
<title></title>
</head><body>
</body>
</html>
Warning: Cannot modify header information - headers already sent by (output started at C:\xampp\htdocs\jiajia\login.php:6) in C:\xampp\htdocs\jiajia\login.php on line 73
第73行的代码是: header("Location: " . $MM_redirectLoginSuccess );
if (isset($_SESSION['PrevUrl']) && false) {
$MM_redirectLoginSuccess = $_SESSION['PrevUrl'];
}
echo "<script>window.location.href='".$MM_redirectLoginSuccess." '</script>";
}下面那句也一样。