为什么会崩溃？

+ (void)load{

    static dispatch_once_t onceToken;

    dispatch_once(&onceToken, ^{

        Class class = [NSURLConnection class];

        SEL selector = @selector(initWithRequest:delegate:);

        SEL swizzledSelector = @selector(test_initWithRequest:delegate:);

        Method originalinitWithRequest = class_getInstanceMethod(class, selector);

        NSURLConnection* (^swizzleBlock)(NSURLConnection *,SEL,NSURLRequest*,id )= ^(NSURLConnection *slf,SEL swizzledSelector,NSURLRequest *request,id delegate) {

            return ((NSURLConnection*(*)(NSURLConnection*,SEL,NSURLRequest*,id))objc_msgSend)(slf,swizzledSelector,request,delegate);

           

        };

       

        IMP implementation = imp_implementationWithBlock(swizzleBlock);

        class_addMethod(class, swizzledSelector, implementation, method_getTypeEncoding(originalinitWithRequest));

        Method newCOnnectionWithRequestClassMethod= class_getInstanceMethod(class, swizzledSelector);

        method_exchangeImplementations(originalinitWithRequest, newConnectionWithRequestClassMethod);

    });

}

(lldb) po slf

{ request: (null) }



(lldb) po swizzledSelector

{ URL: http://httpstat.us/200 }



(lldb) po request





(lldb) po delegate

 nil

2017-12-19 15:09:25.923 HookNetwork2[4030:501650] *** NSForwarding: warning: selector (0x60000000e020) for message 'Xˆü' does not match selector known to Objective C runtime (0x608000004340)-- abort

2017-12-19 15:09:25.924 HookNetwork2[4030:501650] (null): unrecognized selector sent to instance 0x60000000dea0

2017-12-19 15:09:25.928 HookNetwork2[4030:501650] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '(null): unrecognized selector sent to instance 0x60000000dea0'

*** First throw call stack:

(

    0   CoreFoundation                      0x000000010926fb0b __exceptionPreprocess + 171

    1   libobjc.A.dylib                     0x0000000108cd4141 objc_exception_throw + 48

    2   CoreFoundation                      0x00000001092df134 -[NSObject(NSObject) doesNotRecognizeSelector:] + 132

    3   CoreFoundation                      0x00000001091f6840 ___forwarding___ + 1024

    4   CoreFoundation                      0x00000001091f63b8 _CF_forwarding_prep_0 + 120

    5   HookNetwork2                        0x00000001086fc379 __20+[RAObserverer load]_block_invoke_2 + 153

    6   HookNetwork2                        0x00000001086fd6a3 -[ViewController connectTest:] + 1731

    7   UIKit                               0x0000000109694d82 -[UIApplication sendAction:to:from:forEvent:] + 83

    8   UIKit                               0x00000001098195ac -[UIControl sendAction:to:forEvent:] + 67

    9   UIKit                               0x00000001098198c7 -[UIControl _sendActionsForEvents:withEvent:] + 450

    10  UIKit                               0x0000000109818802 -[UIControl touchesEnded:withEvent:] + 618

    11  UIKit                               0x00000001097027ea -[UIWindow _sendTouchesForEvent:] + 2707

    12  UIKit                               0x0000000109703f00 -[UIWindow sendEvent:] + 4114

    13  UIKit                               0x00000001096b0a84 -[UIApplication sendEvent:] + 352

    14  UIKit                               0x0000000109e945d4 __dispatchPreprocessedEventFromEventQueue + 2926

    15  UIKit                               0x0000000109e8c532 __handleEventQueue + 1122

    16  CoreFoundation                      0x0000000109215c01 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17

    17  CoreFoundation                      0x00000001091fb0cf __CFRunLoopDoSources0 + 527

    18  CoreFoundation                      0x00000001091fa5ff __CFRunLoopRun + 911

    19  CoreFoundation                      0x00000001091fa016 CFRunLoopRunSpecific + 406

    20  GraphicsServices                    0x000000010d044a24 GSEventRunModal + 62

    21  UIKit                               0x0000000109693134 UIApplicationMain + 159

    22  HookNetwork2                        0x00000001086ff2bf main + 111

    23  libdyld.dylib                       0x000000010c0d965d start + 1

    24  ???                                 0x0000000000000001 0x0 + 1

)

libc++abi.dylib: terminating with uncaught exception of type NSException