iOS开发-网络-合理封装请求接口（三）真实案例

实际项目开发中会用到的接口多种多样，有一些相对复杂的数据例如：列表、列表嵌套等，这里使用一个真实案例来阐述如何解决

使用GET请求调用API（https://www.sojson.com/open/api/weather/json.shtml），获取“北京市”未来五天天气预报

用浏览器打开该API，可以看到JSON数据格式，最终显示效果如图所示

23.png

---

先建模:

@interface WeatherModel : BaseModel

@property (nonatomic, strong) NSString *api;//161
@property (nonatomic, strong) NSString *date;//19日星期四
@property (nonatomic, strong) NSString *sunrise;//05:33
@property (nonatomic, strong) NSString *sunset;//18:56
@property (nonatomic, strong) NSString *high;//高温 26.0℃
@property (nonatomic, strong) NSString *low;//低温 13.0℃
@property (nonatomic, strong) NSString *type;//多云
@property (nonatomic, strong) NSString *fx;//东南风
@property (nonatomic, strong) NSString *fl;//4-5级
@property (nonatomic, strong) NSString *notice;//阴晴之间，谨防紫外线侵扰

@end

外面一层数据在建模时，需要注意一下其中forecast和yesterday字段对应的类型定义，其中yesterday是WeatherModel类型，forecast数组的每项元素也是WeatherModel类型

@interface CityWeatherModel : BaseModel

@property (nonatomic, strong) NSString *shidu;//73%
@property (nonatomic, strong) NSString *wendu;//17
@property (nonatomic, strong) NSString *pm25;//150
@property (nonatomic, strong) NSString *pm10;//232
@property (nonatomic, strong) NSString *quality;//中度污染
@property (nonatomic, strong) WeatherModel *yesterday;//注意类型
@property (nonatomic, strong) NSArray *forecast;//注意类型

@end

接下来封装业务接口，这里相比第二章中的简单数据解析多了些内容，但是很好理解

1. 定义keyArray和valueArray数组，用于映射responseObj内部数据关系
2. 从刚才建模的步骤，得知yesterday对象和forecast数组元素类型均为WeatherModel，keyArray中存储数据需要映射的Model类型，valueArray中存储被映射的数据字段

重要：keyArray[0,1,…n]和valueArray[0,1,…n]，两数组下标对应的内容必须逐一对应，不可出现元素个数不相等的情况

+ (void)weatherCity:(NSString *)city success:(void(^)(CityWeatherModel *model))success failure:(void(^)(HttpException * e))failure{

    NSString *urlStr = @"[https://www.sojson.com/open/api/weather/json.shtml](https://www.sojson.com/open/api/weather/json.shtml)";

    NSDictionary *requestDic = @{@"city":city};//入参数据

    [HttpClientMgr get:urlStr params:requestDic success:^(id responseObj) {

        NSMutableArray *keyArray = [NSMutableArray array];
        [keyArray addObject:NSStringFromClass([WeatherModel  class])];
        [keyArray addObject:NSStringFromClass([WeatherModel  class])];

        NSMutableArray *valueArray = [NSMutableArray array];
        [valueArray addObject:@"yesterday"];
        [valueArray addObject:@"forecast"];

        CityWeatherModel *model = [CityWeatherModel parse:responseObj ClassArr:keyArray Elements:valueArray]; //NSDictionary -> Model

        if(success){
            success(model);
        }

    } failure:^(HttpException *e) {

        if(failure){
            failure(e);
        }
    }];
}

调用:

[NetworkAPI weatherCity:@"北京" success:^(CityWeatherModel *model) {

    NSArray *dataArr = model.forecast;

} failure:^(HttpException *e) {

}];

如何将数据呈现在界面上这里不再赘述