What is an interface in the context of PHP OOP?
- A contract for
- An abstract class
- A concrete class
- A trait
In PHP OOP, an interface is indeed a contract or a set of rules that defines a specific behavior or functionality. It provides a way to establish a common structure and ensure that classes that implement the interface adhere to that structure. An interface contains only method signatures without implementation. Classes that implement an interface must provide an implementation for all the methods defined in the interface. Interfaces allow for polymorphism and provide a way to define a common interface that multiple classes can adhere to. For further information, visit: http://php.net/manual/en/language.oop5.interfaces.php
A common use case of the include statement in PHP is to include ______.
- reusable code
- database connections
- external APIs
- CSS stylesheets
One of the common use cases of the include statement in PHP is to include reusable code from other files. This allows you to organize your code into separate files and include them as needed, reducing redundancy and promoting code reuse.
What is the meaning of a Persistent Cookie?
- A cookie that never expires
- A cookie that is always secure
- A cookie that is shared across pages
- A cookie that is permanent
A persistent cookie is a type of cookie that is stored on the user's device even after they close their browser. It has an expiration date set in the future. Learn more: http://php.net/manual/en/function.setcookie.php
You are tasked with creating a PHP function that accepts a filename, opens the file, prints its contents, and then closes the file. How would you approach this task?
- Use the fopen() function to open the file, read its contents using fread() or other file reading functions, print the contents, and then close the file using fclose()
- Use the readfile() function to directly output the file contents, and then close the file using fclose()
- Use the file_get_contents() function to read the entire file into a string, print the contents, and then close the file using fclose()
- Use the file() function to read the file line by line into an array, print the contents, and then close the file using fclose()
You can create a PHP function that accepts a filename. Inside the function, you would use fopen() to open the file, fread() or other file reading functions to read its contents, print the contents as desired, and then close the file using fclose(). This ensures proper file handling and cleanup after printing the contents.
What PHP function can be used to write to a file?
- readfile()
- file_get_contents()
- fwrite()
- fopen()
The fwrite() function in PHP is used to write to a file. It takes the file handle obtained from fopen() as the first argument and the content to write as the second argument. It returns the number of bytes written or false on failure.
The same function name can be used for multiple functions in the same PHP script.
- TRUE
- FALSE
Yes, in PHP, you can define multiple functions with the same name in the same script. This is known as function overloading. However, unlike some other programming languages, PHP does not support function overloading by differentiating functions based on the number or type of arguments. The most recently declared function with the same name will be used. Learn more: https://www.php.net/manual/en/functions.user-defined.php
Which of the following are ways to make a field required in a PHP form?
- Using the required attribute in HTML
- Implementing server-side validation in PHP
- Using JavaScript to validate the field on the client-side
- All of the above
All of the above options are ways to make a field required in a PHP form. You can use the required attribute in HTML to enforce client-side validation, ensuring that the field must be filled out before submitting the form. Implementing server-side validation in PHP allows you to check if the required field has been submitted with a value. Using JavaScript on the client-side provides an additional layer of validation to ensure the field is not left empty before submitting the form. It is recommended to use a combination of client-side and server-side validation to ensure the integrity and security of form submissions. Learn more: https://www.php.net/manual/en/tutorial.forms.php
To destroy a session in PHP, you can use the session_destroy() ______.
- function
- method
- statement
- command
To destroy a session in PHP, you can use the session_destroy() function. This function is called as a statement to remove all session data and end the current session. It effectively destroys the session. It's important to note that session_destroy() alone may not unset all session variables, so you may also need to call session_unset() to unset all session variables before calling session_destroy(). Learn more: http://php.net/manual/en/function.session-destroy.php
The filter_var() function with the FILTER_SANITIZE_STRING filter is used to sanitize a string in PHP.
- TRUE
- FALSE
To sanitize a string in PHP, you can use the filter_var() function with the FILTER_SANITIZE_STRING filter. This filter specifically sanitizes the string by removing HTML tags and encoding special characters, making the string safe for output. The filter_var() function provides a convenient and reliable way to sanitize strings in PHP. For more information, see: http://php.net/manual/en/function.filter-var.php
The PHP interpreter executes comments as part of the script.
- TRUE
- FALSE
This statement is false. The PHP interpreter completely ignores comments during the script's execution. Comments are purely for the developers' benefit and do not have any impact on the functioning of the code. They are not executed as part of the script and are not sent to the client's browser. It's important to remember that comments are solely used for documentation purposes and have no effect on the actual program logic. Learn more: https://www.php.net/manual/en/language.basic-syntax.comments.php