#import "MethodForwardTest.h"

#import <objc/runtime.h>

#import "Replacement.h"

@implementation MethodForwardTest

id dynamicMethod(id self, SEL _cmd) {

NSLog(@"首先尝试动态添加方法");

return @"首先尝试动态添加方法";

}

+ (BOOL)resolveInstanceMethod:(SEL)sel {

NSString *selectorString = NSStringFromSelector(sel);

if ([selectorString isEqualToString:@"test"]) {

class_addMethod(self, sel, (IMP)dynamicMethod, "@@:");

}

return YES;

}

- (id)forwardingTargetForSelector:(SEL)aSelector {

return [[Replacement alloc] init];

}

- (void)anotherTest {

NSLog(@"另一个test方法");

}

- (NSMethodSignature *)methodSignatureForSelector:(SEL)aSelector {

NSMethodSignature *signature = [super methodSignatureForSelector:aSelector];

if (!signature) { // 如果不能处理这个方法

if ([self respondsToSelector:@selector(anotherTest)]) {

// 返回另一个函数的方法签名，这个函数不一定要定义在本类中

signature = [MethodForwardTest instanceMethodSignatureForSelector:@selector(anotherTest)];

}

}

return signature;

}

- (void)forwardInvocation:(NSInvocation *)anInvocation {

[anInvocation setSelector:@selector(anotherTest)]; // 设置需要调用的选择子

[anInvocation invokeWithTarget:self]; // 设置消息的接收者，不一定必须是self

}