iOS代码技巧之ASIHttpRequest类库的使用及Json解析(以解析中国天气网天气预报为例）

声明：由于ASIHttpRequest作者已早不进行维护，而且ios版本已经更新到7，为了大家的代码在ios7下能更加高效和保险，建议使用AFNetworking类库，此类库也是ASI的作者所推荐的，如只是学习了解网络方面内容，可以参考本博客，关于AFNetworking的使用，相关博客本人会尽快整理

一、下载ASIHttpRequest的类库和JSONKit类库，添加到工程中

• ASIHttpRequest类库包含文件，还有.m文件，由于名字相同，只列举.h文件
• ，以及Reachability.h和.m文件
• JSONKit中只有JSONKit.h和JSONKit.m两个文件

二、添加framework（参考链接中第十二步）

CFNetwork.framework
SystemConfiguration.framework
MobileCoreServices.framework
CoreGraphics.framework
libz.1.2.3.dylib

三、网络请求

声明URL：此处以镇江为例，更多城市代码

在.m文件中

#import"ASIHttpRequest.h"

#import"JSONKit.h"

#define GET_WEATHER_URL [NSURL URLWithString:@"http://m.weather.com.cn/data/101190301.html"]

在.h文件中声明ASIHttpRequestDelegate

<ASIHTTPRequestDelegate>

在需要请求网络部分添加代码

//定义request
    ASIHTTPRequest *requestWeather = [ASIHTTPRequest requestWithURL:GET_WEATHER_URL];
    //设置代理
    requestWeather.delegate = self;
    //设置请求成功的回调方法，也可设置失败方法didFailSelector，如果调用失败方法，说明未成功，方便自己进行调试和处理
    requestWeather.didFinishSelector = @selector(requestWeatherFinished:);
    //开始异步请求
    [requestWeather startAsynchronous];

完成回调方法（其中的WeatherModal是自定义的一个类，为了方便存储返回的json数据，见下文）

-(void)requestWeatherFinished:(ASIHTTPRequest *)request
{   
    NSDictionary *object = [[request responseString] JSONValue];//获取返回数据，有时有些网址返回数据是NSArray类型，可先获取后打印出来查看数据结构，再选择处理方法，得到所需数据
    //获取object中数据
    NSDictionary *weather = [object objectForKey:@"weatherinfo"];
    weatherModal *modal = [weatherModal alloc] init];//若未使用ARC，记得release
    modal.city = [weather objectForKey:@"city"];  //城市名称
    modal.date_y = [weather objectForKey:@"date_y"];//日期
    // 六天天气
    modal.weather1 = [weather objectForKey:@"weather1"];
    modal.weather2 = [weather objectForKey:@"weather2"];
    modal.weather3 = [weather objectForKey:@"weather3"];
    modal.weather4 = [weather objectForKey:@"weather4"];
    modal.weather5 = [weather objectForKey:@"weather5"];
    modal.weather6 = [weather objectForKey:@"weather6"];

    // 六天风速
    modal.wind1 = [weather objectForKey:@"wind1"];
    modal.wind2 = [weather objectForKey:@"wind2"];
    modal.wind3 = [weather objectForKey:@"wind3"];
    modal.wind4 = [weather objectForKey:@"wind4"];
    modal.wind5 = [weather objectForKey:@"wind5"];
    modal.wind6 = [weather objectForKey:@"wind6"];
    
    // 天气变化
    modal.img_title1 = [weather objectForKey:@"img_title1"];
    modal.img_title2 = [weather objectForKey:@"img_title2"];
    modal.img_title3 = [weather objectForKey:@"img_title3"];
    modal.img_title4 = [weather objectForKey:@"img_title4"];
    modal.img_title5 = [weather objectForKey:@"img_title5"];
    modal.img_title6 = [weather objectForKey:@"img_title6"];
    modal.img_title7 = [weather objectForKey:@"img_title7"];
    modal.img_title8 = [weather objectForKey:@"img_title8"];
    modal.img_title9 = [weather objectForKey:@"img_title9"];
    modal.img_title10 = [weather objectForKey:@"img_title10"];
    modal.img_title11= [weather objectForKey:@"img_title11"];
    modal.img_title12= [weather objectForKey:@"img_title12"];
    // 温度
    modal.temp1 = [weather objectForKey:@"temp1"];
    modal.temp2 = [weather objectForKey:@"temp2"];
    modal.temp3 = [weather objectForKey:@"temp3"];
    modal.temp4 = [weather objectForKey:@"temp4"];
    modal.temp5 = [weather objectForKey:@"temp5"];
    modal.temp6 = [weather objectForKey:@"temp6"];
    modal.week = [weather objectForKey:@"week"];
}

WeatherModal.h，此类是自定义类型，若需要像NSString一样拷贝赋值，只需加上一个方法，请参考自定义类拷贝办法

#import <Foundation/Foundation.h>

@interface weatherModal : NSObject
{
    NSString *_city;
    NSString *_city_en;
    NSString *_cityid;
    NSString *_date;
    NSString *_date_y;

    NSString *_img_single;
    NSString *_img_title1;
    NSString *_img_title10;
    NSString *_img_title11;
    NSString *_img_title12;
    NSString *_img_title2;
    NSString *_img_title3;
    NSString *_img_title4;
    NSString *_img_title5;
    NSString *_img_title6;
    NSString *_img_title7;
    NSString *_img_title8;
    NSString *_img_title9;
    NSString *_img_title_single;
  
    NSString *_temp1;
    NSString *_temp2;
    NSString *_temp3;
    NSString *_temp4;
    NSString *_temp5;
    NSString *_temp6;
   
    NSString *_weather1;
    NSString *_weather2;
    NSString *_weather3;
    NSString *_weather4;
    NSString *_weather5;
    NSString *_weather6;
    NSString *_week;
    NSString *_wind1;
    NSString *_wind2;
    NSString *_wind3;
    NSString *_wind4;
    NSString *_wind5;
    NSString *_wind6;
}
@property(nonatomic,copy) NSString *city;
@property(nonatomic,copy) NSString *city_en;
@property(nonatomic,copy) NSString *cityid;
@property(nonatomic,copy) NSString *date;
@property(nonatomic,copy) NSString *date_y;


@property(nonatomic,copy) NSString *img_single;
@property(nonatomic,copy) NSString *img_title1;
@property(nonatomic,copy) NSString *img_title10;
@property(nonatomic,copy) NSString *img_title11;
@property(nonatomic,copy) NSString *img_title12;
@property(nonatomic,copy) NSString *img_title2;
@property(nonatomic,copy) NSString *img_title3;
@property(nonatomic,copy) NSString *img_title4;
@property(nonatomic,copy) NSString *img_title5;
@property(nonatomic,copy) NSString *img_title6;
@property(nonatomic,copy) NSString *img_title7;
@property(nonatomic,copy) NSString *img_title8;
@property(nonatomic,copy) NSString *img_title9;
@property(nonatomic,copy) NSString *img_title_single;


@property(nonatomic,copy) NSString *temp1;
@property(nonatomic,copy) NSString *temp2;
@property(nonatomic,copy) NSString *temp3;
@property(nonatomic,copy) NSString *temp4;
@property(nonatomic,copy) NSString *temp5;
@property(nonatomic,copy) NSString *temp6;

@property(nonatomic,copy) NSString *weather1;
@property(nonatomic,copy) NSString *weather2;
@property(nonatomic,copy) NSString *weather3;
@property(nonatomic,copy) NSString *weather4;
@property(nonatomic,copy) NSString *weather5;
@property(nonatomic,copy) NSString *weather6;
@property(nonatomic,copy) NSString *week;
@property(nonatomic,copy) NSString *wind1;
@property(nonatomic,copy) NSString *wind2;
@property(nonatomic,copy) NSString *wind3;
@property(nonatomic,copy) NSString *wind4;
@property(nonatomic,copy) NSString *wind5;
@property(nonatomic,copy) NSString *wind6;


@end

weatherModal.m中对这些属性进行synthesize即可

PS：在解析json值时若是值关键字比较多均可定义一个modal进行存储数据，比较方便

附上我做的效果图，天气图片不是解析得到（也可解析得到，安卓成功，但本人ios没有解析成功，原因未知），是自己找好图片后，根据关键字进行匹配放置的

图片共享一下

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