iOS组件化开发入门 —— 提交自己的私有库

@interface Router : NSObject

/*
 通过传递urlStr 将target、action、参数传进来
 */
- (id)openURL:(NSString*)urlStr;


@end


@implementation Router

- (id)openURL:(NSString*)urlStr{
    
    NSURL *url = [NSURL URLWithString:urlStr];
    NSMutableDictionary *params = [[NSMutableDictionary alloc]init];
    //查询http携带的参数
    NSString *parameterString = [url query];
    //切割字符串,转换为键值对
    NSArray * parameterArr = [parameterString componentsSeparatedByString:@"&"];
    for (NSString *param in parameterArr) {
        NSArray *elts = [param componentsSeparatedByString:@"="];
        if (elts.count<2) continue;
        id firstElt = [elts firstObject];
        id lastElt = [elts lastObject];
        if (firstElt && lastElt) {
            [params setObject:lastElt forKey:firstElt];
        }
    }
    NSString *actionName = [url.path stringByReplacingOccurrencesOfString:@"/" withString:@""];
    if ([actionName hasPrefix:@"native"]) {
        return @(NO);
    }
    //将 target 、action 和 参数传递过去
    id result = [self performTarget:url.host action:actionName param:params];
    return result;
}

- (id)performTarget:(NSString *)targetName action:(NSString *)actionName param:(NSDictionary *)para {
    
    //OC反射机制，获取class 和 方法名(方法名要注意是否有冒号)
    NSString *targetClassString = [NSString stringWithFormat:@"Target_%@",targetName];
    NSString *actionMethondString = [NSString stringWithFormat:@"action_%@:",actionName];
    Class targetClass = NSClassFromString(targetClassString);
    //确定target 和 action
    NSObject *target = [[targetClass alloc] init];
    SEL action = NSSelectorFromString(actionMethondString);
    
    // 排除不响应的情况
    if ([target respondsToSelector:action]) {
        return [self safePerformAction:action target:target param:para];
    } else {
        SEL action = NSSelectorFromString(@"notFound:");
        if ([target respondsToSelector:action]) {
             return [self safePerformAction:action target:target param:para];
        } else {
            return nil;
        }
    }
    return nil;
}
/**
 调用指定对象的指定方法完成命令的响应
 @param action 方法
 @param target 目标对象
 @param para 参数
 @return 返回值
 */
- (id)safePerformAction:(SEL)action target:(NSObject *)target param:(NSDictionary *)para {
    //方法签名
    NSMethodSignature *methodSig = [target methodSignatureForSelector:action];
    if (methodSig == nil) {
        return nil;
    }
    // 获取这个方法返回值
    const char *retType = [methodSig methodReturnType];
    NSInvocation *invocation = [NSInvocation invocationWithMethodSignature:methodSig];
    [invocation setArgument:&para atIndex:2];
    [invocation setTarget:target];
    [invocation setSelector:action];
    [invocation invoke];
    // id是可以返回任意对象,所以单独处理基本变量: NSInteger Bool ...
    if (strcmp(retType, @encode(NSInteger)) == 0||
        strcmp(retType, @encode(BOOL)) == 0||
        strcmp(retType, @encode(CGFloat)) == 0) {
        NSInteger result = 0;
        [invocation getReturnValue:&result];
            return @(result);
    }
    else if (strcmp(retType, @encode(void)) == 0){
        return nil;
    }
    else{
        id result;
        [invocation getReturnValue:&result];
        return result;
    }
}

@end