Objective-C Data Types

In the Objective-C programming language, data types refer to an extensive system used for declaring variables or functions of different types. The type of a variable determines how much space it occupies in storage and how the bit pattern stored is interpreted.

The types in Objective-C can be classified as follows −

The array types and structure types are referred to collectively as the aggregate types. The type of a function specifies the type of the function s return value. We will see basic types in the following section whereas other types will be covered in the upcoming chapters.

Integer Types

Following table gives you details about standard integer types with its storage sizes and value ranges −

To get the exact size of a type or a variable on a particular platform, you can use the sizeof operator. The expression sizeof(type) yields the storage size of the object or type in bytes. Following is an example to get the size of int type on any machine −

#import <Foundation/Foundation.h>

int main() {
   NSLog(@"Storage size for int : %d 
", sizeof(int));
   return 0;
}

2013-09-07 22:21:39.155 demo[1340] Storage size for int : 4 

#import <Foundation/Foundation.h>

int main() {
   NSLog(@"Storage size for float : %d 
", sizeof(float));
   return 0;
}

2013-09-07 22:22:21.729 demo[3927] Storage size for float : 4