Backend Development
PHP Tutorial
Driving skills for newbies on the road PHP newbies on the road (7)
Driving skills for newbies on the road PHP newbies on the road (7)
Build a simple interactive website (3)
6. Password verification
Perhaps you want to put your photo collection on your website and only want to show it to your close friends. In this case, you need a password verification program.
6.1 Based on HTTP verification
How to use PHP to implement password verification? We can use short PHP code to force authentication by sending an HTTP header using the function header(), and the client browser will pop up a dialog box for entering the username and password. In PHP, the information entered by the client user is automatically saved in the three global variables $PHP_AUTH_USER, $PHP_AUTH_PW, and $PHP_AUTH_TYPE after it is transmitted to the server. Using these variables, we can authenticate the user's identity based on the user account information that the implementation saves in a data file or database.
However, users need to be reminded here that only when running in Apache module mode, PHP scripts can use the three variables $PHP_AUTH_USER, $PHP_AUTH_PW, and $PHP_AUTH_TYPE. If the user is using PHP in CGI mode, the HTTP-based authentication function cannot be implemented.
6.2 Next, we will introduce in detail how to use PHP to verify user identity.
In the following example, we use the two variables $PHP_AUTH_USER and $PHP_AUTH_PW to verify whether the entrant is legal and allow entry. In this example, the user name and password pairs allowed to log in are tnc and nature respectively:
if(!isset($PHP_AUTH_USER))
{
Header("WWW-Authenticate: Basic realm="My Realm" ");
Header("HTTP/1.0 401 Unauthorized");
echo "Text to send if user hits Cancel buttonn";
exit;
}
else
{
if ( !($PHP_AUTH_USER=="tnc" && $PHP_AUTH_PW=="nature") )
{
// If it is a wrong username/password pair, force re-authentication
Header("WWW-Authenticate: Basic realm="My Realm"");
Header("HTTP /1.0 401 unauthorized ");
Echo" error: $ php_auth_user/$ php_auth_pw is invalid. "; & gt; References are unlikely to use explicit username/password pairs as in the snippet above, but instead use a database or encrypted password file to access them.
6.3 Verify user identity based on specified verification information
First, we can use the following code to determine whether the user has entered the username and password, and display the information entered by the user.
if (!isset($PHP_AUTH_USER)) {
header('WWW-Authenticate: Basic realm="My Private Stuff"');
header('HTTP/1.0 401 Unauthorized');
echo ' Authorization Required.';
exit;
}
else {
echo "
You have entered this username: $PHP_AUTH_USER
You have entered this password: $PHP_AUTH_PW
The authorization type is: $ PHP_AUTH_TYPE
}
?>
Description: The
isset() function is used to determine whether a variable has been assigned a value. Returns true or false depending on whether the variable value exists.
header() function is used to send specific HTTP headers. Note that when using the header() function, be sure to call it before any HTML or PHP code that produces the actual output.
Although the above code is quite simple and does not effectively validate the username and password entered by the user based on any actual values, at least we understand how to use PHP to generate an input dialog box on the client side.
Next, let’s take a look at how to verify the user’s identity based on the specified verification information. The code is as follows:
if (!isset($PHP_AUTH_USER)) {
header('WWW-Authenticate: Basic realm="My Private Stuff"');
header('HTTP/1.0 401 Unauthorized');
echo 'Authorization Required.';
exit;
}
else if (isset($PHP_AUTH_USER)) {
if (($PHP_AUTH_USER != "admin") || ($PHP_AUTH_PW != "123")) {
header('WWW-Authenticate: Basic realm="My Private Stuff"');
header('HTTP/1.0 401 Unauthorized');
echo 'Authorization Required.';
exit;
} else {
echo "< You're authorized! information. Subsequently, we grant the user access rights or prompt the user to enter the correct information again by determining whether the information entered by the user matches the specified user account admin/123. This method works for sites where all users use the same login account.
6.4 Another simple password verification
If you write and run your PHP script under Windows 98, or if you install PHP as a CGI program according to the default settings under Linux, you will not be able to use the above PHP program to implement the verification function. For this reason, Wubian provides you with another simple password verification method.Although it is not very practical, it is still good for learning.
$password = "123";
// check password
if($pass != $password)
{
echo "
echo "
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
Explain JSON Web Tokens (JWT) and their use case in PHP APIs.
Apr 05, 2025 am 12:04 AM
JWT is an open standard based on JSON, used to securely transmit information between parties, mainly for identity authentication and information exchange. 1. JWT consists of three parts: Header, Payload and Signature. 2. The working principle of JWT includes three steps: generating JWT, verifying JWT and parsing Payload. 3. When using JWT for authentication in PHP, JWT can be generated and verified, and user role and permission information can be included in advanced usage. 4. Common errors include signature verification failure, token expiration, and payload oversized. Debugging skills include using debugging tools and logging. 5. Performance optimization and best practices include using appropriate signature algorithms, setting validity periods reasonably,
How does session hijacking work and how can you mitigate it in PHP?
Apr 06, 2025 am 12:02 AM
Session hijacking can be achieved through the following steps: 1. Obtain the session ID, 2. Use the session ID, 3. Keep the session active. The methods to prevent session hijacking in PHP include: 1. Use the session_regenerate_id() function to regenerate the session ID, 2. Store session data through the database, 3. Ensure that all session data is transmitted through HTTPS.
What are Enumerations (Enums) in PHP 8.1?
Apr 03, 2025 am 12:05 AM
The enumeration function in PHP8.1 enhances the clarity and type safety of the code by defining named constants. 1) Enumerations can be integers, strings or objects, improving code readability and type safety. 2) Enumeration is based on class and supports object-oriented features such as traversal and reflection. 3) Enumeration can be used for comparison and assignment to ensure type safety. 4) Enumeration supports adding methods to implement complex logic. 5) Strict type checking and error handling can avoid common errors. 6) Enumeration reduces magic value and improves maintainability, but pay attention to performance optimization.
Describe the SOLID principles and how they apply to PHP development.
Apr 03, 2025 am 12:04 AM
The application of SOLID principle in PHP development includes: 1. Single responsibility principle (SRP): Each class is responsible for only one function. 2. Open and close principle (OCP): Changes are achieved through extension rather than modification. 3. Lisch's Substitution Principle (LSP): Subclasses can replace base classes without affecting program accuracy. 4. Interface isolation principle (ISP): Use fine-grained interfaces to avoid dependencies and unused methods. 5. Dependency inversion principle (DIP): High and low-level modules rely on abstraction and are implemented through dependency injection.
Explain late static binding in PHP (static::).
Apr 03, 2025 am 12:04 AM
Static binding (static::) implements late static binding (LSB) in PHP, allowing calling classes to be referenced in static contexts rather than defining classes. 1) The parsing process is performed at runtime, 2) Look up the call class in the inheritance relationship, 3) It may bring performance overhead.
What is REST API design principles?
Apr 04, 2025 am 12:01 AM
RESTAPI design principles include resource definition, URI design, HTTP method usage, status code usage, version control, and HATEOAS. 1. Resources should be represented by nouns and maintained at a hierarchy. 2. HTTP methods should conform to their semantics, such as GET is used to obtain resources. 3. The status code should be used correctly, such as 404 means that the resource does not exist. 4. Version control can be implemented through URI or header. 5. HATEOAS boots client operations through links in response.
How do you handle exceptions effectively in PHP (try, catch, finally, throw)?
Apr 05, 2025 am 12:03 AM
In PHP, exception handling is achieved through the try, catch, finally, and throw keywords. 1) The try block surrounds the code that may throw exceptions; 2) The catch block handles exceptions; 3) Finally block ensures that the code is always executed; 4) throw is used to manually throw exceptions. These mechanisms help improve the robustness and maintainability of your code.
What are anonymous classes in PHP and when might you use them?
Apr 04, 2025 am 12:02 AM
The main function of anonymous classes in PHP is to create one-time objects. 1. Anonymous classes allow classes without names to be directly defined in the code, which is suitable for temporary requirements. 2. They can inherit classes or implement interfaces to increase flexibility. 3. Pay attention to performance and code readability when using it, and avoid repeatedly defining the same anonymous classes.
