我有以下代码来进行方法调配:
static inline void swizzleMethod(const char *clsName, const char *mthName, const char *clsName2, const char *mthName2) {
Class cls1 = objc_getClass(clsName);
SEL sel1 = sel_registerName(mthName);
Class cls2 = objc_getClass(clsName2);
SEL sel2 = sel_registerName(mthName2);
Method mth = class_getInstanceMethod(cls2, sel2);
IMP imp = method_getImplementation(mth);
NSLog(@"method type encoding %s", method_getTypeEncoding(mth));
class_replaceMethod(cls1, sel1, imp, method_getTypeEncoding(mth));
}
我的 VGFileHandle 类:
@interface VGFileHandle : NSObject
@end
@implementation VGFileHandle
- (NSData *)readDataToEndOfFile {
NSLog(@"readDataToEndOfFile");
return nil;
}
@end
在 main.m 中,我有以下调用:
int main(int argc, char *argv[])
{
swizzleMethod("NSFileHandle", "readDataToEndOfFile", "VGFileHandle", "readDataToEndOfFile");
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *filePath = [documentsDirectory stringByAppendingPathComponent:@"myFile"];
NSFileHandle *handle = [NSFileHandle fileHandleForReadingAtPath:filePath];
NSData *data = [handle readDataToEndOfFile];
@autoreleasepool {
return UIApplicationMain(argc, argv, nil, NSStringFromClass([AppDelegate class]));
}
}
正确的,当调用 [handle readDataToEndOfFile] 时,它应该从 VGFileHandle 调用 readDataToEndOfFile 并打印出“readDataToEndOfFile”。但是,在我的测试项目中,方法调配似乎根本没有取代方法实现。[handle readDataToEndOfFile] 仍然执行原始实现。
我想知道可能是什么原因。提前致谢。