How to swizzle []method of NSArray in iOS11?

Question

I used to hack the method like

Method originalMethod = class_getInstanceMethod([NSArray class], @selector(objectAtIndexedSubscript:));
Method swapMethod = class_getInstanceMethod([NSArray class], @selector(objectAtIndexedSubscriptNew:));
method_exchangeImplementations(originalMethod, swapMethod);

It works fine in the iOS10 and before, but it can't work in the iOS11, is that any other way we can swizzle the [] method in iOS11?

Answer 1

As of iOS 11, for some reason that I'm still researching, swizzle methods should only be called once.

static dispatch_once_t once;
dispatch_once(&once, ^{    
    Method originalMethod = class_getInstanceMethod([NSArray class], @selector(objectAtIndexedSubscript:));
    Method swapMethod = class_getInstanceMethod([NSArray class], @selector(objectAtIndexedSubscriptNew:));
    method_exchangeImplementations(originalMethod, swapMethod);
});

Answer 2

我将类从[NSArray class]更改为NSClassFromString(@"__NSArrayI")并且它现在工作正常。