Effective OBJECTIVE-C 2.0 first day of study

Important knowledge point personal understanding record

The first article: OC is the message structure language, runtime parsing, compile-time not care

Article Two: Introduction of the head file try not to. h file (compilation trouble), where to import, generally in. m import. Don't forget that @class can be declared in the. h file.

Article Three: multi-use simplified syntax, such as nsarray *a = @[@ "x", @ "XX"]; for variable arrays [@[@ "S", @ "SS"] mutablecopy];

Fourth: Less defining constants with # define. static nsstring *const xxx = @ "222";

. h file

#import "BaseViewController.h"

Static const int kwidth = 3;

Static const int khigh;

extern nsstring *const constkey;

@interface constviewcontroller: baseviewcontroller

@end

. m file

#import "ConstViewController.h"

const int khight = +;

NSString *const Constkey = @ "111";

@interface constviewcontroller ()

@end

@implementation Constviewcontroller

-(void) viewdidload {

[Super viewdidload];

}

-(void) didreceivememorywarning {

[Super didreceivememorywarning];

}

@end

Effective OBJECTIVE-C 2.0 first day of study