使用AlamofireObjectMapper

XINNYU

2016-02-14

iOS, 第三方库

通常网络请求返回的是JSON数据，使用ObjectMapper可以让JSON数据直接转化为对象，而使用Alamofire进行网络请求时，使用AlamofireObjectMapper可以直接返回对象，更加简洁。

###CocoaPods 导入AlamofireObjectMapper

'AlamofireObjectMapper', '~> 3.0'```


这里采用的Alamofire的测试接口 https://httpbin.org/get
在浏览器中打开可以看到JSON格式的数据：
```JSON
{
  "args": {}, 
  "headers": {
    "Accept": "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8", 
    "Accept-Encoding": "gzip, deflate, br", 
    "Accept-Language": "zh-CN,zh;q=0.8,en-US;q=0.5,en;q=0.3", 
    "Cache-Control": "max-age=0", 
    "Host": "httpbin.org", 
    "User-Agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.11; rv:46.0) Gecko/20100101 Firefox/46.0"
  }, 
  "origin": "202.115.52.218", 
  "url": "https://httpbin.org/get"
}

根据该JSON的数据格式创建以下两个Mapper类分别对应整个字典和key值为“header”的字典。将JSON中的数据与对象中的数据一一建立转化关系。

import Foundation
import ObjectMapper
class ResponseHeader: Mappable {
    var accept : String?
    var acceptEncoding : String?
    var acceptLanguage : String?
    var cacheControl : String?
    var host : String?
    var userAgent : String?
    required init?(_ map: Map) {
    }
    //映射heades字典中的所有键值
    func mapping(map: Map) {
        accept <- map["Accept"]
        acceptEncoding <- map["Accept-Encoding"]
        acceptLanguage <- map["Accept-Language"]
        cacheControl <- map["Cache-Control"]
        host <- map["Host"]
        userAgent <- map["User-Agent"]
    }
}

import Foundation
import ObjectMapper
class MyResponse: Mappable {
    var args : NSDictionary?
    var headers : ResponseHeader?
    var origin : String?
    var url : String?
    required init?(_ map: Map) {
    }
    //映射字典中的所有键值
    func mapping(map: Map) {
        args <- map["args"]
        headers <- map["headers"]
        origin <- map["origin"]
        url <- map["url"]
    }
}

用Alamofire获取对象

func webRequst()  {
    let url = "https://httpbin.org/get"
    //注意返回的类型为<Mappable对象,NSError>
    Alamofire.request(.GET, url).responseObject { (response: Response<MyResponse, NSError>) in
        let myResponse = response.result.value
        print(myResponse?.url)
        if let header = myResponse?.headers{
            print(header.userAgent)
        }
    }
}