从Objective-C中的方法返回多个值 [英] Returning multiple values from a method in Objective-C

问题描述

我问了一个类似的问题，但我无法让它完全正常工作。我正在构建一个iPhone应用程序，我想从不同的文件调用一个方法。我认为最简单的方法就是在另一个文件中创建一个方法，并从其他文件中调用该方法。

I asked a similar question, but I couldn't get it working exactly. I'm building an iPhone app, and there is a method that I want called from different files. I figured the easiest way would simply be to make a method in another file, and call the method from the other files.

这是一些问题。我需要在传递多个值后从该方法返回多个值。例如，我传递它：（int，int，int，string，string）。并且它们需要在更改后返回所有这些值。有人向我展示了这段代码：

Here are some problems. I need to return multiple values from the method, after passing it multiple values. For example, I'm passing it: (int, int, int, string, string). And it needs to return all of those values, after they have been changed. Someone showed me this code:

- (NSDictionary *)EndOfTurn:(int)varTurns withFatness:(int)varFatness
{
    varTurns--;

    if (varTurns <= 0) {
        varFatness = varFatness - 5;
    }
    else {
        varFatness += 2;
    }

    return [NSDictionary dictionaryWithObjectsAndKeys:[NSNumber numberWithInt:varFatness], @"FATNESS", [NSNumber numberWithInt:varTurns], @"TURNS", nil];

}

但是，此代码不起作用，我需要更多信息，以真正了解它。让我们假设我传递了这些值：

However, this code doesn't work, and I need some more information to really understand it. Let's assuming I'm passing it these values:

int varMoney;
int varNumSheep;
int varNumShepherds;
NSString *test1;
NSString *test2;

所以我需要从方法中获取所有这些值。

So I need to get all of these values back from the method.

如何在头文件中声明这一点？这应该是一个Objective-C文件，但你可以给我整个文件的代码，这样我就可以看到 @implementation 和 @end ，等等。另外，我如何调用此方法？

How do I declare this in the header file? This should be in an Objective-C file, but could you give me the code for the entire file so I can see where it would go with the @implementation and @end, whatnot. Also, how would I call this method?

推荐答案

因为您只能从C和C-中的任何方法返回单个值派生语言，您只需返回一个代表所有其他值的值。这是您的示例代码使用 NSDictionary 进行的操作。

Since you can only return a single value from any method in C and C-derived languages, you simply need to return a single value that represents all of your other values. This is what your sample code is doing with an NSDictionary.

示例代码是正确的，即使它是一个与常见的Objective-C风格相反。

The sample code is correct, even if it's a bit contrary to common Objective-C style.

您在头文件中声明的只是方法的声明，即：

What you declare in the header file is simply the declaration of the method, that is:

@interface MyClass : NSObject
- (NSDictionary *)EndOfTurn:(int)varTurns withFatness:(int)varFatness;
@end

在源文件中，然后：

@implementation MyClass
// code, as given above
@end

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