使用$ _session选择数据

Question

我为学校的课程构建了一个小脚本，它将更新数据库中的用户详细信息。

我的更新脚本有效，但是我想实现的是在php中使用会话变量选择数据。

该生产线的问题是：

$query = mysql_query ("SELECT * from customer where username = 'ryan'"); 

我宁愿它读取类似：

$query = mysql_query ("SELECT * from customer where username = $_SESSION['myusername']"); 

但是，这是行不通的。会话从我的登录表单传递，可以在页面上显示用户名，但在我的select语句中不起作用。

这里是我的代码：

<?php 
session_start(); 

$con = mysql_connect("localhost","root","root"); 
if (!$con) 
{ 
die('Could not connect: ' . mysql_error()); 
} 

mysql_select_db("ryandb", $con); 

echo "welcome ". $_SESSION['myusername'] . " to the members only page</br>"; 


$query = mysql_query ("SELECT * from customer where username = 'ryan'"); 


while ($row = mysql_fetch_array ($query)) 
{ 
    $username = $row['username']; 
    $firstname = $row['firstname']; 
    $surname = $row['surname']; 
    $email = $row['email']; 
} 

?> 

<form method="post" action="updateuser.php"> 
Username: <input type="text" name="username" value="<?php echo $_SESSION['myusername']; ? >" /><br /> 
Firstname: <input type="text" name="firstname" value="<?php echo $firstname; ?>"/><br /> 
Surname: <input type="text" name="surname" value="<?php echo $surname; ?>"/><br /> 
Email: <input type="text" name="email" value="<?php echo $email; ?>"/><br /> 
<input type= "submit" name = "update" value="Update"> 
</form> 

Answer 1

//$query = mysql_query ("SELECT * from customer where username = $_SESSION['myusername']"); 

试试这个

$query = mysql_query ("SELECT * from customer where username = '$_SESSION['myusername']'"); 

Answer 2

使用此查询。

$query = mysql_query ("SELECT * from customer where username = '".$_SESSION['myusername']."'");