The extract() Function is an inbuilt function in PHP. The extract() function does
array to variable conversion
. That is it converts array keys into variable names and array values into variable value. In other words, we can say that the extract() function imports variables from an array to the symbol table.
What is the use of extract () and compact () function?
The compact() function is an inbuilt function in PHP and it is used
to create an array using variables
. This function is opposite of extract() function. It creates an associative array whose keys are variable names and their corresponding values are array values.
Is PHP extract safe?
Its
dangerous
to use extract in global scope and for _REQUEST, _GET, _POST, _COOKIE. However if you allow only the variables you are going to use by use of a filtering mechanism and unset everything that comes from outside, you can use extract.
How does PHP Isset work?
The isset() function is an inbuilt function in PHP which
checks whether a variable is set and is not NULL
. This function also checks if a declared variable, array or array key has null value, if it does, isset() returns false, it returns true in all other possible cases.
What is implode and explode function in PHP?
The explode() function breaks a string into an array, but the implode function
returns a string from the elements of an array
. For example, you have a string.
What is the correct way of declaring PHP variable?
A
variable starts with the $ sign, followed by the name of the variable
. A variable name must start with a letter or the underscore character. A variable name cannot start with a number. A variable name can only contain alpha-numeric characters and underscores (A-z, 0-9, and _ )
What is PHP call function?
A function is a
self-contained block of code that performs a specific task
. PHP has a huge collection of internal or built-in functions that you can call directly within your PHP scripts to perform a specific task, like gettype() , print_r() , var_dump , etc.
What is the full form of PHP?
PHP (recursive acronym for
PHP: Hypertext Preprocessor
) is a widely-used open source general-purpose scripting language that is especially suited for web development and can be embedded into HTML.
How do you declare an associative array in PHP?
Associative Array – It refers
to an array with strings as an index
. Rather than storing element values in a strict linear index order, this stores them in combination with key values. Multiple indices are used to access values in a multidimensional array, which contains one or more arrays.
What are the different operators in PHP?
- Arithmetic Operators.
- Assignment Operators.
- Bitwise Operators.
- Comparison Operators.
- Incrementing/Decrementing Operators.
- Logical Operators.
- String Operators.
- Array Operators.
Does exist in PHP?
The
file_exists()
function in PHP is an inbuilt function which is used to check whether a file or directory exists or not. The path of the file or directory you want to check is passed as a parameter to the file_exists() function which returns True on success and False on failure.
Is empty in PHP?
PHP empty() Function
The empty() function checks whether a variable is empty or not. This function returns false if the variable exists and is not empty, otherwise it returns true.
Is set method in PHP?
PHP
isset() Function
The isset() function checks whether a variable is set, which means that it has to be declared and is not NULL. This function returns true if the variable exists and is not NULL, otherwise it returns false.
What is the use of Print_r in PHP?
The print_r() function is a built-in function in PHP and is used
to print or display information stored in a variable
.
How many types of arrays are there in PHP?
There are basically
three types
of arrays in PHP: Indexed or Numeric Arrays: An array with a numeric index where values are stored linearly. Associative Arrays: An array with a string index where instead of linear storage, each value can be assigned a specific key.
Is in array in PHP?
The
in_array
() function is an inbuilt function in PHP. The in_array() function is used to check whether a given value exists in an array or not. It returns TRUE if the given value is found in the given array, and FALSE otherwise.
