What is the use of static variables and why do we use them?

Static variables, by contrast, are variables associated with a class itself, rather than a particular instance of that class. Static variables are used to keep track of information that relates logically to an entire class, as opposed to information that varies from instance to instance.

How do you set a static variable in Objective C?

Here’s what you do:

1. In your header file, declare class methods to use as accessors:
2. At the top of your implementation file, declare a static variable to hold the value:
3. In the implementation section for your class, write your accessors:

What does a static variable do?

Static variables reduce the amount of memory used by a program. Static variables are shared among all instances of a class. Non static variables are specific to that instance of a class. Static variable is like a global variable and is available to all methods.

What is static function in C?

A static function in C is a function that has a scope that is limited to its object file. This means that the static function is only visible in its object file. A function can be declared as static function by placing the static keyword before the function name.

When should you use static variables?

use static variables when : The value of the variable is independent of the objects (not unique for each object). E.g. number of students. Static variable: When you need something that will be used through out the application and every instance need to know the variable.

How do you declare a variable in Objective-C?

Variable Declaration in Objective-C You will use extern keyword to declare a variable at any place. Though you can declare a variable multiple times in your Objective-C program but it can be defined only once in a file, a function or a block of code.

How do you declare a global variable in Objective-C?

Somewhere in your header, you would declare a global variable like this: extern int GlobalInt; The extern part tells the compiler that this is just a declaration that an object of type int identified by GlobalInt exists.

What is static variable and static function?

When static keyword is used, variable or data members or functions can not be modified again. Static functions can be called directly by using class name. Static variables are initialized only once. Compiler persist the variable till the end of the program. Static variable can be defined inside or outside the function.

Why static variable is used in C?

In the C programming language, static is used with global variables and functions to set their scope to the containing file. In local variables, static is used to store the variable in the statically allocated memory instead of the automatically allocated memory.