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Question: What is the use of the "this" keyword in PHP?
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Answer: The "this" keyword refers to the current instance of the class.
It is used to access properties and methods of the current object within a class.
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Question: Can you explain the purpose of the spl_autoload_register() function in PHP?
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Answer: The 'spl_autoload_register()' is used for autoloading classes in PHP.
It registers a function or method to be called automatically when a class is accessed and not yet defined,
allowing dynamic loading of classes as needed.
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Question: How can you upload files in PHP?
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Answer: Files can be uploaded in PHP using the '$_FILES' superglobal along with HTML forms having enctype="multipart/form-data".
PHP provides functions like 'move_uploaded_file()' to handle file uploads securely.
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Question: What is the use of the "static" keyword in PHP?
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Answer: The "static" keyword in PHP is used to declare properties and methods of a class as static.
Static properties and methods can be accessed directly without creating an instance of the class.
They are shared among all instances of the class.
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Question: Explain the difference between "echo" and "print" in PHP?
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Answer: Both "echo" and "print" are used to output data in PHP.
The main difference is that "echo" can output multiple parameters at once, whereas "print" can only output
one parameter and always returns 1.
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Question: What is the purpose of the 'header()' function in PHP?
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Answer: The 'header()' function in PHP is used to send HTTP headers to the client browser.
It is commonly used for tasks such as redirecting users to another page, setting cookies, and specifying the content type of the page.
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Question: Can you explain how sessions work in PHP?
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Answer: The Sessions in PHP allow you to store user data on the server, identified by a session ID stored
in a cookie or passed via URL.
This data persists across multiple page requests until the session is destroyed.
Sessions are commonly used for tasks such as user authentication and maintaining user-specific data.
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Question: What are magic methods in PHP? Provide examples?
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Answer: The Magic-methods are special methods with predefined names that are automatically called when
certain actions occur in a class, like:
'__construct()' for object initialization.
'__get()' and '__set()' for accessing and setting properties dynamically.
'__toString()' for converting an object to a string.
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Question: Can you explain the difference between 'include_once()' and 'require_once()' functions in PHP?
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Answer: Both 'include_once()' and 'require_once()' are similar to 'include()' and 'require()' functions,
respectively. But they check if the file has already been included or required to prevent duplicate inclusions.
If the file has already been included or required, it will not be included or required again.
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