PHP session application instance logon Verification

Last Update:2018-12-08 Source: Internet

Author: User

Tags php session

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CopyCode The Code is as follows: <HTML>
<Head>
<Title> login </title>
<Meta http-equiv = "Content-Type" content = "text/html; charset = gb2312">
</Head>

<Body>
<Form name = "form1" method = "Post" Action = "login. php">
<Table width = "300" border = "0" align = "center" cellpadding = "2" cellspacing = "2">
<Tr>
<TD width = "150"> <Div align = "right"> User name: </div> </TD>
<TD width = "150"> <input type = "text" name = "username"> </TD>
</Tr>
<Tr>
<TD> <Div align = "right"> password: </div> </TD>
<TD> <input type = "password" name = "passcode"> </TD>
</Tr>
<Tr>
<TD> <Div align = "right"> cookie retention time: </div> </TD>
<TD> <select name = "cookie" id = "cookie">
<Option value = "0" selected> browser Process </option>
<Option value = "1"> Save for 1 day </option>
<Option value = "2"> Save for 30 days </option>
<Option value = "3"> 365 days </option>
</SELECT> </TD>
</Tr>
</Table>
<P align = "center">
<Input type = "Submit" name = "Submit" value = "Submit">
<Input type = "reset" name = "reset" value = "reset">
</P>
</Form>
</Body>
</Html>

Copy code The Code is as follows: <? PHP
@ Mysql_connect ("localhost", "root", "1981427") // You must connect to the database server before selecting a database.
Or die ("database server connection failed ");
@ Mysql_select_db ("test") // select the database mydb
Or die ("the database does not exist or is unavailable ");
// Obtain user input
$ Username = $ _ post ['username'];
$ Passcode = $ _ post ['passcode'];
// Execute an SQL statement to obtain the session Value
$ Query = @ mysql_query ("select username, userflag from users"
. "Where username = '$ username' and passcode =' $ passcode '")
Or die ("SQL statement execution failed ");
// Determine whether the user exists and the password is correct
If ($ ROW = mysql_fetch_array ($ query ))
{
Session_start (); // indicates the start of the session.
// Determine whether the user's permission information is valid. If the value is 1 or 0, the permission information is valid.
If ($ row ['userflag'] = 1 or $ row ['userflag'] = 0)
{
$ _ Session ['username'] = $ row ['username'];
$ _ Session ['userflag'] = $ row ['userflag'];
Echo "<a href =" Main. php "href =" Main. php "> welcome to log on. Click here to go to the welcome page </a> ";
}
Else // output error message if the permission information is invalid
{
Echo "incorrect user permission information ";
}
}
Else // if the user name and password are incorrect, an error is returned.
{
Echo "incorrect user name or password ";
}
?>

Copy codeThe Code is as follows: <? PHP
Unset ($ _ session ['username']);
Unset ($ _ session ['passcode']);
Unset ($ _ session ['userflag']);
Echo "logout successful ";
?>

Copy code The Code is as follows: <? PHP
Session_start ();
If (isset ($ _ session ['username'])
{
@ Mysql_connect ("localhost", "root", "1981427") // You must connect to the database server before selecting a database.
Or die ("database server connection failed ");
@ Mysql_select_db ("test") // select the database mydb
Or die ("the database does not exist or is unavailable ");
// Obtain the session
$ Username = $ _ session ['username'];
// Execute the SQL statement to obtain the userflag Value
$ Query = @ mysql_query ("select userflag from users"
. "Where username = '$ username '")
Or die ("SQL statement execution failed ");
$ ROW = mysql_fetch_array ($ query );
// Compare the permission information in the current database with that in the session. If the permission information is different, update the session information.
If ($ row ['userflag']! = $ _ Session ['userflag'])
{
$ _ Session ['userflag'] = $ row ['userflag'];
}
// Output different welcome information based on the session Value
If ($ _ session ['userflag'] = 1)
Echo "Welcome administrator". $ _ session ['username']. "log on to the system ";
If ($ _ session ['userflag'] = 0)
Echo "welcome". $ _ session ['username']. "log on to the system ";
Echo "<a href =" logout. php "href =" logout. php "> logout </a> ";
}
Else
{
Echo "You are not authorized to access this page ";
}
?>

This article is an English version of an article which is originally in the Chinese language on aliyun.com and is provided for information purposes only. This website makes no representation or warranty of any kind, either expressed or implied, as to the accuracy, completeness ownership or reliability of the article or any translations thereof. If you have any concerns or complaints relating to the article, please send an email, providing a detailed description of the concern or complaint, to info-contact@alibabacloud.com. A staff member will contact you within 5 working days. Once verified, infringing content will be removed immediately.

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