小编Min*_*ava的帖子

无论是否使用x += 1或建议我都很困惑x = x+1.我知道他们都产生了相同的结果.实际上,使用时x+=1代替是否有任何性能提升x = x+1？它会让我的程序运行得更快吗？

我正在使用Xcode iOS SDK 6.1制作计算器.但是,我遇到了一个问题,因为我的计算器无法将两个数字加在一起.似乎计算器总是给我第一个数字作为答案.有办法解决问题吗？

这是代码:

#import "ViewController.h"


@interface ViewController ()

@end

@implementation ViewController
@synthesize FirstNumber,SecondNumber;

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    self.FirstNumber.delegate = self;
    self.SecondNumber.delegate = self;

}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

- (void)dealloc
{
    [FirstNumber release];
    [SecondNumber release];

    [super dealloc];
}

- (IBAction)Calculate:(id)sender
{
    NSString *finalNumberString;
    int firstNumberInt, secondNumberInt, finalNumberInt;

    firstNumberInt = [FirstNumber.text integerValue];
    secondNumberInt = …