我已经创建了一个NSURLConnection和NSURLSession类别，因此我会在运行时拦截调用并收集网络信息。
除非我使用NSURLConnection
sendAsynchronousRequest:queue:completionHandler:
sendSynchronousRequest:returningResponse:error:
这两种静态方法在我的调配中不服从，而在调试时我发现方法实现交换正在发生，正如我调的其他方法一样。 这是我的代码，类似于我对其他似乎工作得很好的方法所做的。
typedef void (^SendAsynchronousCompletionHandlerBlock)(NSURLResponse*, NSData*, NSError*);
static void (*OriginalNSURLConnectionSendAsynchronousRequestQueueCompletionHandler)(id, SEL, NSURLRequest*, NSOperationQueue*, SendAsynchronousCompletionHandlerBlock);
static NSData* (*OriginalNSURLConnectionSendSynchronousRequestReturningResponseError)(id, SEL, NSURLRequest*, NSURLResponse**, NSError**);
static void MyNSURLConnectionSendAsynchronousRequestQueueCompletionHandler(id self, SEL _cmd, NSURLRequest* request, NSOperationQueue* queue, SendAsynchronousCompletionHandlerBlock completionHandler)
{
NSLog(@"Implementation Intercept in %s", __PRETTY_FUNCTION__);
OriginalNSURLConnectionSendAsynchronousRequestQueueCompletionHandler(self, _cmd, request, queue, completionHandler);
}
static NSData* MyNSURLConnectionSendSynchronousRequestReturningResponseError(id self, SEL _cmd, NSURLRequest* request, NSURLResponse** response, NSError** error)
{
NSLog(@"Implementation Intercept in %s", __PRETTY_FUNCTION__);
NSData* data = OriginalNSURLConnectionSendSynchronousRequestReturningResponseError(self, _cmd, request, response, error);
return data;
}
@implementation NSURLConnection (MyNSURLConnection)
+ (void) load
{
// Create onceToken
static dispatch_once_t onceToken;
// Use dispatch_once to make sure this runs only once in the lifecycle
dispatch_once(&onceToken,
^{
NSLog(@"Injecting code to NSURLConnection");
[self injectImplementationToNSURLConnectionSendAsynchronousRequestQueueCompletionHandler];
[self injectImplementationToNSURLConnectionSendSynchronousRequestReturningResponseError];
// Some other methods I intercept, just as reference, they work as tested to init an NSURLConnection object
// I will skip their implementation which is similar to what I show here
[self injectImplementationToNSURLConnectionConnectionWithRequestDelegate];
[self injectImplementationToNSURLConnectionInitWithRequestDelegateStartImmediately];
[self injectImplementationToNSURLConnectionInitWithRequestDelegate];
[self injectImplementationToNSURLConnectionStart];
});
}
+ (void) injectImplementationToNSURLConnectionSendAsynchronousRequestQueueCompletionHandler
{
// Replace the method on the same class that's used
// in the calling code
Class class = [NSURLConnection class];
// The Original +sendAsynchronousRequest:queue:completionHandler:
SEL originalSelector = @selector(sendAsynchronousRequest:queue:completionHandler:);
// The Replacement method implementation
IMP replacement = (IMP)MyNSURLConnectionSendAsynchronousRequestQueueCompletionHandler;
// This will eventually hold the original sendAsynchronousRequest:queue:completionHandler:
IMP* store = (IMP*)&OriginalNSURLConnectionSendAsynchronousRequestQueueCompletionHandler;
IMP originalImp = NULL;
Method method = class_getClassMethod(class, originalSelector);
if (method)
{
const char* type = method_getTypeEncoding(method);
// Replace the original method with the MyNSURLConnectionSendAsynchronousRequestQueueCompletionHandler
originalImp = class_replaceMethod(class, originalSelector, replacement, type);
if (!originalImp)
{
originalImp = method_getImplementation(method);
}
}
// Put the original method IMP into the pointer
if (originalImp && store)
{
*store = originalImp;
}
}
+ (void) injectImplementationToNSURLConnectionSendSynchronousRequestReturningResponseError
{
// Replace the method on the same class that's used
// in the calling code
Class class = [NSURLConnection class];
// The Original +sendSynchronousRequest:returningResponse:error: selector
SEL originalSelector = @selector(sendSynchronousRequest:returningResponse:error:);
// The Replacement method implementation
IMP replacement = (IMP)MyNSURLConnectionSendSynchronousRequestReturningResponseError;
// This will eventually hold the original sendSynchronousRequest:returningResponse:error:
IMP* store = (IMP*)&OriginalNSURLConnectionSendSynchronousRequestReturningResponseError;
IMP originalImp = NULL;
Method method = class_getClassMethod(class, originalSelector);
if (method)
{
const char* type = method_getTypeEncoding(method);
// Replace the original method with the MyNSURLConnectionSendSynchronousRequestReturningResponseError
originalImp = class_replaceMethod(class, originalSelector, replacement, type);
if (!originalImp)
{
originalImp = method_getImplementation(method);
}
}
// Put the original method IMP into the pointer
if (originalImp && store)
{
*store = originalImp;
}
}
那么是什么使我可以使用不同的方法将我的代码转移到原始实现中，并且没有任何错误发生。
以下是我测试的代码：
- (IBAction) executeURLRequest: (UIButton*)sender
{
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:@"https://My.URL/file.json"]];
[request setValue:@"API_KEY" forHTTPHeaderField:@"X-My-Auth-Token"];
NSURLResponse* response;
NSError* error;
// Doesn't work, my swizzle method is not invoked
[NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&error];
// Doesn't work, my swizzle method is not invoked
[NSURLConnection sendAsynchronousRequest:request queue:[NSOperationQueue currentQueue] completionHandler:
^(NSURLResponse *response, NSData *data, NSError *error)
{
if (error) NSLog(@"NSURLConnection failed: %@", [error debugDescription]);
NSLog(@"Made the NSURLRequest to My");
}];
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_LOW, 0),
^{
// It works, I get to see my message of the method invoked to the output console
NSURLConnection* connection = [[NSURLConnection alloc] initWithRequest:request delegate:nil startImmediately:YES];
});
}
我不知道，对我来说看起来还不错......你觉得怎么样？
答案 0 :(得分：2)
首先，不要在调试和/或学习目的之外调配系统框架方法。它是脆弱的，将打破操作系统的版本，并且在发现时不会批准或删除混合系统框架的应用程序。
其次，最有可能的情况是NSURLConnection被实现为类集群。因此，可能有一些子类实现了实际的连接，并且你正在调整抽象的超级实现，它什么都不做。
答案 1 :(得分：2)
虽然你需要特别小心调整，但我并不知道苹果公司禁止调整系统框架的任何政策。我自己也在调试这些相同的类，SDK已经包含在应用商店的应用中。
虽然NSURLSession是。
，但NSURLConnection并未实现为类集群我创作了在Apigee iOS SDK中调配NSURLConnection和NSURLSession的代码。在这里看看NSURLConnection的混合实现：
答案 2 :(得分：0)
这是我的代码，我能够调用（void）sendAsynchronousRequest：（NSURLRequest *）请求队列：（NSOperationQueue ）队列completionHandler：（void（^）（NSURLResponse ，NSData *， NSError *））处理
// + (void)sendAsynchronousRequest:(NSURLRequest *)request queue:(NSOperationQueue *)queue completionHandler:(void (^)(NSURLResponse*, NSData*, NSError*))handler
void (*gOrigNSURLConnection_sendAsynchronousRequestQueueCompletionHandler)(id,SEL,NSURLRequest *,NSOperationQueue *,DataTaskCompletionBlock) = NULL;
static void NSURLConnection_logTelemetrySendAsynchronousRequestQueueCompletionHandler(id self, SEL _cmd, NSURLRequest* request, NSOperationQueue* queue, DataTaskCompletionBlock completionHandler)
{
NSLog(@"i am catched");
return gOrigNSURLConnection_sendAsynchronousRequestQueueCompletionHandler( self, _cmd ,request,queue,completionHandler);
}
// in swizzling method
// NSURLConnection + (void)sendAsynchronousRequest:queue:completionHandler:
selMethod = @selector(sendAsynchronousRequest:queue:completionHandler:);
impOverrideMethod = (IMP) NSURLConnection_logTelemetrySendAsynchronousRequestQueueCompletionHandler;
origMethod = class_getClassMethod(c,selMethod);
gOrigNSURLConnection_sendAsynchronousRequestQueueCompletionHandler = (void *)method_getImplementation(origMethod);
if( gOrigNSURLConnection_sendAsynchronousRequestQueueCompletionHandler != NULL )
{
method_setImplementation(origMethod, impOverrideMethod);
++numSwizzledMethods;
} else {
NSLog(@"error: unable to swizzle + (void)sendAsynchronousRequest:queue:completionHandler:");
}
我的测试代码
- (IBAction)clickSendAsyncWithBlock:(id)sender {
NSURL *URL = [NSURL URLWithString:@"http://localhost:8000/a.txt"];
NSURLRequest *request = [NSURLRequest requestWithURL:URL cachePolicy:NSURLRequestReloadIgnoringLocalCacheData timeoutInterval:60];
[NSURLConnection sendAsynchronousRequest:request
queue:[NSOperationQueue mainQueue]
completionHandler:^(NSURLResponse *response, NSData *data, NSError *error) {
NSString *myString = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
NSLog(@"got %@" , myString);
}];
}
结果：