iOS 处理方法中的可变參数

Posted 2020-06-15

## ios 处理方法中的可变參数

      近期写了一个自己定义的对话框的demo，想模仿系统的UIAlertView的实现方式。对处理可变參数的时候，遇到了小问题，于是谷歌了一下。写下了处理问题的方法。记录下来，以备后需。

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代码实现

- (instancetype)initWithTitle:(NSString *)title message:(NSString *)message delegate:(id)delegate cancelButtonTitle:(NSString *)cancelButtonTitle otherButtonTitles:(NSString *)otherButtonTitles, ... {
    if (self = [super init]) {
        self.title = title;
        self.delegate = delegate;
        self.frame = CYScreen.bounds;
        // 获取可变參数的值
        if (![self isBlankString:cancelButtonTitle]) {
            [self.buttonTitles addObject:cancelButtonTitle];
        }
        NSString *str;
        va_list list;
        if(otherButtonTitles)
        {
            // 1.取得第一个參数的值
            CYLog(@"%@", otherButtonTitles);
            [self.buttonTitles addObject:otherButtonTitles];
            // 2.从第2个參数開始。依此取得全部參数的值
            va_start(list, otherButtonTitles);
            while ((str = va_arg(list, NSString *))){
                CYLog(@"%@", str);
                [self.buttonTitles addObject:str];
            }
            va_end(list);
        }
        CYLog(@"%@", self.buttonTitles);
    }
    return self;
}

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方法调用

- (IBAction)showDialog {
    CYAlertView *alert = [[CYAlertView alloc]initWithTitle:@"我的提示" message:@"消息正文" delegate:self cancelButtonTitle:@"取消" otherButtonTitles:@"确定", @"XXX", @"YYY", nil];
    alert.containerView = [self createDemoView];
    [alert show];
}

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打印结果

2015-07-06 15:54:26.422 CYCustomAlertView[358:42937] 确定
2015-07-06 15:54:26.424 CYCustomAlertView[358:42937] XXX
2015-07-06 15:54:26.424 CYCustomAlertView[358:42937] YYY
2015-07-06 15:54:26.425 CYCustomAlertView[358:42937] (
    取消,
    确定,
    XXX,
    YYY,
)