oc动态方法绑定

绑定多个参数

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//传递三个及以上的参数 - (id)performSelector:(SEL)selector withObjects:(NSArray *)objects { // 方法签名(方法的描述) NSMethodSignature *signature = [[self class] instanceMethodSignatureForSelector:selector]; if (signature == nil) { //可以抛出异常也可以不操作。 } // NSInvocation : 利用一个NSInvocation对象包装一次方法调用（方法调用者、方法名、方法参数、方法返回值） NSInvocation *invocation = [NSInvocation invocationWithMethodSignature:signature]; invocation.target = self; invocation.selector = selector; // 设置参数 NSInteger paramsCount = signature.numberOfArguments - 2; // 除self、_cmd以外的参数个数 paramsCount = MIN(paramsCount, objects.count); for (NSInteger i = 0; i < paramsCount; i++) { id object = objects[i]; if ([object isKindOfClass:[NSNull class]]) continue; [invocation setArgument:&object atIndex:i + 2]; } // 调用方法 [invocation invoke]; // 获取返回值 id returnValue = nil; if (signature.methodReturnLength) { // 有返回值类型，才去获得返回值 [invocation getReturnValue:&returnValue]; } return returnValue; }

执行objc_msgsend

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- (void)ObjcMsgSend { NSString *str = @"字符串"; NSNumber *num = @20; NSArray *arr = @[@"v1", @"v2"]; SEL sel = NSSelectorFromString(@"ObjcMsgSendWithString:withNum:withArray:"); ((void (*) (id, SEL, NSString *, NSNumber *, NSArray *)) objc_msgSend) (self, sel, str, num, arr); } // 执行方法 - (void)ObjcMsgSendWithString:(NSString *)string withNum:(NSNumber *)number withArray:(NSArray *)array { NSLog(@"%@, %@, %@", string, number, array[0]); }