对NSURLSession进行网络请求方法封装

//
//  HJURLSession.h
//  HJURLSession
//
//  Created by 黄健 on 16/3/29.
//  Copyright © 2016年 黄健. All rights reserved.
//

#import <Foundation/Foundation.h>

typedef enum {
GET,
POST
} RequestMethod;

typedef void(^ResponseBlock)(id responseObject);
typedef void(^ErrorBlock)(id error);

@interface HJURLSession : NSObject

/**
*  @author 黄健, 2016-05-26 16:05:59
*
*  @brief 对NSURLSession进行封装的网络请求类
*
*  @param _string   请求接口
*  @param _method   请求方式
*  @param _params   请求参数
*  @param _response 响应成功Block返回的数据
*  @param _error    响应失败Block返回的数据
*/
+ (void)sessionWithString:(NSString *)_string method:(RequestMethod)_method params:(NSDictionary *)_params
response:(ResponseBlock)_response error:(ErrorBlock)_error;

@end

//
//  HJURLSession.m
//  HJURLSession
//
//  Created by 黄健 on 16/3/29.
//  Copyright © 2016年 黄健. All rights reserved.
//

#import "HJURLSession.h"

@implementation HJURLSession

+ (void)sessionWithString:(NSString *)_string method:(RequestMethod)_method params:(NSDictionary *)_params
response:(ResponseBlock)_response error:(ErrorBlock)_error
{
NSString *string;

// 将字典类型的请求参数转化为字符串
NSString *params = [HJURLSession paramsToString:_params];

// 下面是根据接口文档的"实际情况"对接口进行拼接，请自行处理
if (_method == GET) {
string = [NSString stringWithFormat:@"%@%@?%@", HOSTNAME, _string, params];
} else {
string = [NSString stringWithFormat:@"%@%@", HOSTNAME, _string];
}

// 对接口进行URL的编码
string = [string stringByAddingPercentEncodingWithAllowedCharacters:[NSCharacterSet URLQueryAllowedCharacterSet]];

NSURL *URL = [NSURL URLWithString:string];

NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:URL];

if (_method == GET) {
[request setHTTPMethod:@"GET"];
} else {
[request setHTTPMethod:@"POST"];
[request setHTTPBody:[params dataUsingEncoding:NSUTF8StringEncoding]];
}

[[[NSURLSession sharedSession] dataTaskWithRequest:request completionHandler:^(NSData * _Nullable data, NSURLResponse * _Nullable response, NSError * _Nullable error) {
if (!error) {
_response([NSJSONSerialization JSONObjectWithData:data options:kNilOptions error:nil]);
} else {
_error(error);
}
}] resume];
}

+ (NSString *)paramsToString:(NSDictionary *)dic
{
NSMutableArray *array = [NSMutableArray array];
for (NSString *key in dic) {
NSString *value = [dic objectForKey:key];
[array addObject:[NSString stringWithFormat:@"%@=%@", key, value]];
}
return [array componentsJoinedByString:@"&"];
}

@end

/**
*  @author 黄健, 2016-05-26 16:05:33
*
*  @brief 对首页接口进行GET请求，并要求显示第一页的5条数据
*/

NSDictionary *params = @{@"page":@"1",
@"page_size":@"5"};

[HJURLSession sessionWithString:@"index" method:GET params:params response:^(id responseObject) {

NSLog(@"%@", responseObject);

} error:^(id error) {
NSLog(@"%@", error);
}];