ios - ARC 不允许将非 Objective-C 指针类型 void* 隐式转换为 NSString*__strong*

Question

迁移到 ARC 时出现上述错误。这是代码:

static NSString *cashBalanceKeyPath = @"test";

...

[xxx forKeyPath:cashBalanceKeyPath options:NSKeyValueObservingOptionNew context:&cashBalanceKeyPath];

...

-(void)observeValueForKeyPath:(NSString *)keyPath
                      ofObject:(id)object
                        change:(NSDictionary *)change
                       context:(void *)context {

    if (&cashBalanceKeyPath == context)   < error here
    {
      ...
    }

当我使用网桥时:

if (&cashBalanceKeyPath == (__bridge NSString *)context)

我收到错误:Comparison of distinct pointer types (NSString *__strong* and NSString *)

如何进行转换？提前致谢。

Answer 1

我不能告诉你确切原因，但如果你交换比较的顺序，你不会收到警告或错误:

if (context == &cashBalanceKeyPath) {
    // ...      
}