PHP notes One

First, Login Login Verification Steps:

1, assigns the value, uses the $_post to pass the ID and the password to the loginprocess.php login Authentication page.

2. Establish database connection $conn =mysql_connect ($host, $username, $password);

3, select Database mysql_select_db (empmanage);

4. Define SQL statement $sql = "Select password from admin";

5. Execute SQL statements and get results $res =mysql_query ($sql, $conn);

6, the comparison password (conditional statement)

If ($row =mysql_fetch_assco ($res)) {

If ($password = $row [' password ']) {

The validation succeeds and jumps to the specified page.

Header ("Location:emp.php");

Exit ();

}else{

Validation failed, return to landing page.

Header ("Location:login.php?error=1");

Exit ();

}

}

7. Release of resources mysql_free_result ($res);

8, close the connection (can be automatic) mysql_close ($conn);

Second, PHP several principles of writing:

1, where the resources from where to release from

2. Close the connection

3, layered thinking —————— very important.

4, the function can only return one result.

Third, object-oriented programming, packaging common tool classes.

(see php folder)

Four, Cookies Knowledge points  

1. How to create a cookie?

The Setcookie () function is used to set cookies.

Note: the Setcookie () function must precede the

Grammar:

Setcookie (name, value, expire, path, domain);

Comments:

2. How do I retrieve the value of a Cookie?

PHP's $_cookie variable is used to retrieve the value of the COOKIE.

Example: In the following example, we use the Isset () function to confirm whether a cookie has been set:

<body>

<?php

if (Isset ($_cookie["user"))

echo "Welcome". $_cookie["User"]. "!  <br/> "; The cookie itself is a hyper-global array;

Else

echo "Cookie no longer exists <br/>";

?>

</body>

3, if the input of Chinese, then the browser will be UrlEncode re-encoding, the same can be used to decode UrlDecode.

Example: <?php echo urldecode ("%c9%cf++%ba%a3");?>

Five, Time Zone Issues

Question: Using the date () function in PHP, why is it 8 hours apart from the current local time?

Method One:
Date_default_timezone_set (' PRC ');
no return value. It's OK to use the date function directly below
$time = Date (Y. ") Year ". M." Month ". D." Day ". G. " When ". I." Points ");

Method Two :

Modify php.ini; date.timezone = Date.timezone = "Asia/shanghai" (or change to Date.timezone = PRC) and remove the preceding semicolon and restart Apache.

PHP notes One