Dark Horse Programmer---iOS learning log 12

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1. Storage details of objects

class to create objects, each object in memory occupies a certain amount of storage space, each object has a separate member variable, all the object common class member method, method in the whole memory only one copy, the class itself in memory occupies a storage space, the method of class exists here.

Example:

#import <Foundation/Foundation.h>

Person.h file

@interface Person:nsobject

{

int _age;

NSString *_name;

}

-(void) run;

@end

PERSON.M file

@implementation person

-(void) run{

NSLog (@ "people running");

}

@end

int main (int argc, const char * argv[]) {
@autoreleasepool {

Person *pe = [person new];

Pe.name = @ "Xue-li";

Pe.age = 18;

NSLog (@ "Name:%@, Age:%d", pe.name,pe.age);

[PE run];

[Person new]; three things to do

1. Apply for memory space

2. Initialize the instantiated variable.

3. Return to the first address of the space

Question 1: Which area of the memory is applied for space?

New when applying space in the heap area of memory (the program dynamically allocates memory space)

Initialized to 0 if the instance variable is the base data type at the time of initialization

If the OC string type is initialized to null

2: Instance variables are saved in the declaration place?

Heap pointer variables are stored in the stack area

Question 3: Where is the object method saved?

Code Area

}
return 0;
}

Dark Horse Programmer---iOS learning log 12