IOS 将类的声明，类的定义，主函数分开放的代码。

类的声明

//
//  Fraction.h
//  0826-类2
//
//  Created by panba on 15-8-27.
//  Copyright (c) 2015年 panba. All rights reserved.
//

#import <Foundation/Foundation.h>

@interface Fraction : NSObject
@property int numberation,donomination;
-(void) print;
-(double) convertToNum;
@end

类的定义

//
// Fraction.m
// 0826-类2
//
// Created by panba on 15-8-27.
// Copyright (c) 2015年 panba. All rights reserved.
//

#import "Fraction.h"

@implementation Fraction
@synthesize numberation,donomination;
-(void) print
{
NSLog(@"%i,%i",numberation,donomination);
}
-(double)convertToNum
{
if (donomination!=0) {
return (double)numberation/donomination;
}
else
{
return NAN;
}
}
@end


主函数
//
// main.m
// 0826-类2
//
// Created by panba on 15-8-27.
// Copyright (c) 2015年 panba. All rights reserved.
//

#import <Foundation/Foundation.h>
#import "Fraction.h"

int main(int argc, const char * argv[]) {
@autoreleasepool {
Fraction *myfrac = [[Fraction alloc] init];
[myfrac setNumberation:5];
[myfrac setDonomination:88];
[myfrac print];
NSLog(@"the result is %lf",[myfrac convertToNum]);
}
return 0;
}