How can I use the filesize function to get the size of a file in PHP? Example code:

$file = "/path/to/file.txt";

$file_size = filesize($file);

echo $file_size;

How can I read data from a JSON file using PHP? Example code:

How can I add days to a date in PHP? Example code:

How can I use the htmlentities function to convert special characters to HTML entities in PHP? Example code:

How can I use the curl_setopt function to set options for a cURL session in PHP? Example code:

How can I use the json_decode function to convert a JSON string to an array or object in PHP? Example code:

How can I subtract days from a date in PHP? Example code:

How can I use the array_unique function to remove duplicate elements from an array in PHP? Example code:

How can I check if a variable is set in PHP? Example code:

How can I prevent SQL injection in PHP?

How can I redirect to another page in PHP? Example code:

How can I shuffle an array in PHP? Example code:

How can I use the curl_exec function to execute a cURL session and get the response in PHP? Example code:

How can I use the explode function to split a string into an array in PHP? Example code:

How can I use the rename function to rename a file or directory in PHP? Example code:

How can I convert a string to lowercase in PHP? Example code:

How can I replace a substring in a string in PHP? Example code:

How can I validate a form using PHP? Example code

How can I use the glob function to get a list of files that match a pattern in PHP? Example code:

How can I use the file_put_contents function to write a string to a file in PHP? Example code:

How can I sort an array in PHP? Example code:

How can I use the array_push function to add an element to an array in PHP? Example code:

How can I check if a string ends with a certain substring in PHP? Example code:

How can I check if a string starts with a certain substring in PHP? Example code:

How can I generate a random string in PHP? Example code:

How can I generate a random number in PHP? Example code

How can I upload a file using PHP? Example code

How can I use the is_readable function to check if a file is readable in PHP? Example code:

How can I check if a string contains a certain substring in PHP? Example code:

How can I use the array_reverse function to reverse the order of an array in PHP? Example code:

How can I use the array_shift function to remove the first element from an array in PHP? Example code: