在Objective-C中，为什么增加4而不是1？

Question

在Objective-C中，我有一个简单的代码块，每次按下按钮都会增加一个计数器。我的日志，甚至是界面的更新，都显示增量为4而不是1。这只是我格式化的显示问题（我正在使用％d）或其他我错过的东西？我的猜测在于“％d”，但我是Objective-C的新手，并不确定。 （注意，我也试过“counter + = 1;”，结果相同。

int counterValue = 0;
NSLog(@"Count at init: %d",counterValue);
...

-(IBAction)pushButton { 
    NSLog(@"Count (Pre-Push) = %d",counterValue);
    counterValue++;
    NSLog(@"Count (Post-Push) = %d",counterValue);
}

输出如下：

2010-02-20 18:39:39.125 My App[37536:207] Count at init:  0
2010-02-20 18:39:39.845 My App[37536:207] Count (Pre-Push) = 0
2010-02-20 18:39:39.846 My App[37536:207] Count (Post-Push) = 4
2010-02-20 18:39:40.165 My App[37536:207] Count (Pre-Push) = 4
2010-02-20 18:39:40.166 My App[37536:207] Count (Post-Push) = 8
2010-02-20 18:39:40.727 My App[37536:207] Count (Pre-Push) = 8
2010-02-20 18:39:40.728 My App[37536:207] Count (Post-Push) = 12

Answer 1

您展示的代码不应该这样做。我做了一个快速的程序来进行双重检查，我得到了预期的结果：

2010-02-22 17:04:35.787 app[68267:a0f] Count (Pre-Push) = 0
2010-02-22 17:04:35.790 app[68267:a0f] Count (Post-Push) = 1
2010-02-22 17:04:35.923 app[68267:a0f] Count (Pre-Push) = 1
2010-02-22 17:04:35.924 app[68267:a0f] Count (Post-Push) = 2

我最好的猜测是，您使用另一个counterValue类型的变量隐藏了int *，这使得+增加了sizeof(int)而不是1。