隐式循环

定义一个Photo类，并带有2个draw方法, 一个带参数、一个不带参数。

Photo.h

#import <Foundation/Foundation.h>

@interface Photo : NSObject {
@private
   
}

-(void) draw;
-(void) draw:(NSNumber*) number;

@end

Photo.m

#import "Photo.h"

@implementation Photo


- (id)init
{
    self = [super init];
    if (self) {
        // Initialization code here.
    }
    
    return self;
}

- (void)dealloc
{
    [super dealloc];
}

-(void) draw
{
    [self draw:[NSNumber numberWithInt:(arc4random() % 100)]];

}

-(void) draw:(NSNumber *)number
{
    NSLog(@"%@", number);
}

@end

main.m

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

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

    NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];

    //创建Photo数组
    NSArray *photos = [NSArray arrayWithObjects:[[Photo alloc] init],[[Photo alloc] init], nil];
    
    //不带参数
    [photos makeObjectsPerformSelector:@selector(draw)];//这里不用有:，是因为没有参数
    
    //带参数
    [photos makeObjectsPerformSelector:@selector(draw:) withObject:[NSNumber numberWithInt:(arc4random() % 101 +100)]];
    
    [pool drain];
    return 0;
}

结果：

[Switching to process 4348 thread 0x0]
2011-05-10 10:34:23.036 demo01[4348:903] 85
2011-05-10 10:34:23.039 demo01[4348:903] 33
2011-05-10 10:34:23.040 demo01[4348:903] 153
2011-05-10 10:34:23.040 demo01[4348:903] 153