Which of the following is not a magic constant in PHP?
- __FILE__
- __DIR__
- __FUNCTION__
- __VARIABLE__
Magic constants in PHP are predefined constants, such as __FILE__, __DIR__, and __FUNCTION__, which provide information about the code's context. __VARIABLE__ is not a valid magic constant.
How do you access the second element of an indexed array named $colors?
- $colors[1]
- $colors[0]
- $colors.second()
- $colors.element(2)
In PHP, arrays are zero-indexed, so the second element of an indexed array is accessed using "$colors[1]".
Which PHP function is particularly useful for validating and filtering data coming from insecure sources?
- filter_var()
- isset()
- htmlentities()
- array_push()
The filter_var() function in PHP is particularly useful for validating and filtering data coming from insecure sources. It allows you to apply various filters, such as validating email addresses or sanitizing input, to ensure that the data is safe and adheres to the desired format.
In PHP, how can you prevent file caching when reading a file?
- Use file_get_contents() with caching disabled
- Use fopen() with the appropriate caching flags
- Set appropriate headers using the header() function
- Use readfile() with caching options
To prevent file caching when reading a file in PHP, you can set appropriate headers using the header() function. This approach instructs the client not to cache the file. Options 1 and 2 do not specifically address caching.
What is the correct way to define a user-defined function in PHP?
- function myFunction() { }
- def myFunction():
- public function myFunction() {}
- def func myFunction():
In PHP, a user-defined function is defined using the 'function' keyword, followed by the function name and parentheses for parameters. The function body is enclosed in curly braces.
If you want to include rows in a JOIN operation where there is no match in both tables, you would use a ________ JOIN.
- INNER
- OUTER
- SELF
- CROSS
To include rows where there's no match in both tables, you would use an "OUTER JOIN." This type of join includes unmatched rows from at least one of the tables.
It's considered good practice to keep your PHP code and HTML ________ to make the code more maintainable.
- Separate
- Combined
- Nested
- Parallel
It's good practice to keep your PHP code and HTML separate. This separation, often achieved with the Model-View-Controller (MVC) pattern, enhances code maintainability by segregating logic (PHP) from presentation (HTML).
How can you prevent a class from being inherited by another class in PHP?
- Declare it as 'final'
- Declare it as 'static'
- Declare it as 'const'
- Declare it as 'sealed'
To prevent a class from being inherited, you declare it as 'final.' The 'final' keyword indicates that the class cannot be extended by other classes.
You are developing a web application where users can submit comments. Which of the following techniques would you implement to ensure that malicious scripts aren't executed when other users view the comments?
- Input Validation and Sanitization
- Server-Side Rendering (SSR)
- Using Base64 Encoding
- Implementing Captcha Verification
Input Validation and Sanitization are key to preventing Cross-Site Scripting (XSS) attacks. These techniques ensure that user input is thoroughly checked and sanitized to prevent the execution of malicious scripts when displaying comments. SSR, Base64 encoding, and Captcha are useful in other contexts but do not directly prevent XSS.
Which superglobal array is used to access session variables in PHP?
- $_GET
- $_POST
- $_SESSION
- $_COOKIE
The superglobal array used to access session variables in PHP is $_SESSION. It stores session data that can be accessed across multiple pages during a user's session.