數據存儲之iOS斷點續傳

• iOS裏面實現斷點續傳
• 第三方框架之AFN
• 代碼實現

1、iOS裏面實現斷點續傳

1⃣️AFN基於NSURL

1.性能和穩定性略差。針對JSON、XML、Plist和Image四種數據結構封裝了各自處理器

2.適合邏輯簡單的應用，易用性好

2⃣️ASI基於CFNetwork（更底層）

1.性能和穩定性略高，沒有針對任何一種數據類型作封裝

2.適合已經發展了一段時間的應用

---

2、第三方框架AFN

1⃣️操做

1.拖入AFN框架文件，編譯（兩個警告，須要倒入框架）

2.倒入System～， Mobile～

3.Supporting File文件修改.pch文件，＃import一下上面兩個框架

2⃣️步驟

1. 指定下載文件地址
2. 指定文件保存路徑
3. 建立NSURLRequest
4. 建立AFURLConnectionOperation
5. 設置操做的輸入流（網絡上數據是以輸入的形式傳輸）
6. 設置下載進程處理塊代碼
7. 操做完成塊代碼
8. 啓動操做

---

3、代碼實現

#pragma mark - 下載文件
- (IBAction)downloadFiles:(id)sender
{
    // 1.   指定下載文件地址
    NSURL *url = [NSURL URLWithString:@"http://169.254.98.245/download/iTunesConnect_DeveloperGuide_CN.zip"];
    // 2.   指定文件保存路徑
    NSArray *documents = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *downloadPath = [documents[0]stringByAppendingPathComponent:@"book.zip"];
    // 3.   建立NSURLRequest
    NSURLRequest *request = [NSURLRequest requestWithURL:url];
    // 4.   建立AFURLConnectionOperation
    AFURLConnectionOperation *operation = [[AFHTTPRequestOperation alloc]initWithRequest:request];
    
    // 5.   設置操做的輸出流（在網絡中的數據是以流的方式傳輸的，告訴操做把文件保存在第2步設置的路徑中）
    [operation setOutputStream:[NSOutputStream outputStreamToFileAtPath:downloadPath append:NO]];
    // 6.   設置下載進程處理塊代碼
    // 6.1 bytesRead 讀取的字節——這一次下載的字節數
    // 6.2 totalBytesRead 讀取的總字節——已經下載完的
    // 6.3 totalBytesExpectedToRead 但願讀取的總字節——就是文件的總大小
    [operation setDownloadProgressBlock:^(NSUInteger bytesRead, long long totalBytesRead, long long totalBytesExpectedToRead) {
        // 作下載進度百分比的工做
        NSLog(@"下載百分比：%f", (float)totalBytesRead / totalBytesExpectedToRead);
    }];
    // 7.   操做完成塊代碼
    [operation setCompletionBlock:^{
        // 解壓縮的順序
        // 1. 定義要解壓縮的文件 —— downloadPath
        // 2. 要解壓縮的目標目錄
        // 3. 調用類方法解壓縮
        [SSZipArchive unzipFileAtPath:downloadPath toDestination:documents[0]];
        
        // 刪除壓縮包
        [[NSFileManager defaultManager]removeItemAtPath:downloadPath error:nil];
    }];
    
    // 8   啓動操做
    [operation start];
}

經常使用方法實現

//
//  ViewController.m
//  AFN框架
//
//  Created by apple on 14-6-21.
//  Copyright (c) 2014年 Early. All rights reserved.
//

#import "ViewController.h"
#import "AFNetworking.h"

@interface ViewController () <NSXMLParserDelegate>
{
    NSOperationQueue *_queue;
    
    UIImageView *_imageView;
}
@end

@implementation ViewController

/**
 1.在Linux系統上，運行的Web服務器叫作Apache
 2.全部的http訪問都是基於html或者相關的文件，例如：php，asp，jsp，asp.net
 3.form，在html頁面中又稱表單，用來提交頁面的，全部post請求的頁面，至少會有一個表單
 4.get／post，get是拿數據，post是將數據體放置在表單中提交給服務器，而後服務器再響應
 */

- (void)viewDidLoad
{
    [super viewDidLoad];
    
    _queue = [[NSOperationQueue alloc] init];
    
    //1.檢測鏈接狀態
    UIButton *btn = [UIButton buttonWithType:UIButtonTypeCustom];
    btn.frame = CGRectMake(100, 100, 100, 50);
    [btn setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
    [btn setTitle:@"連接狀態" forState:UIControlStateNormal];
    [btn addTarget:self action:@selector(reach) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:btn];
    
    //2.JSON解析
    UIButton *btn2 = [UIButton buttonWithType:UIButtonTypeCustom];
    btn2.frame = CGRectMake(100, 150, 100, 50);
    [btn2 setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
    [btn2 setTitle:@"加載JSON" forState:UIControlStateNormal];
    [btn2 addTarget:self action:@selector(loadJSON) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:btn2];
    
    //3.XML解析
    UIButton *btn3 = [UIButton buttonWithType:UIButtonTypeCustom];
    btn3.frame = CGRectMake(100, 200, 100, 50);
    [btn3 setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
    [btn3 setTitle:@"加載XML" forState:UIControlStateNormal];
    [btn3 addTarget:self action:@selector(loadXML) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:btn3];
    
    //4.UIImageView
    UIButton *btn4 = [UIButton buttonWithType:UIButtonTypeCustom];
    btn4.frame = CGRectMake(100, 250, 100, 50);
    [btn4 setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
    [btn4 setTitle:@"加載UIImageView" forState:UIControlStateNormal];
    [btn4 addTarget:self action:@selector(loadImageView) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:btn4];
    
    //5.上傳文件
    UIButton *btn5 = [UIButton buttonWithType:UIButtonTypeCustom];
    btn5.frame = CGRectMake(100, 300, 100, 50);
    [btn5 setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
    [btn5 setTitle:@"上傳圖像" forState:UIControlStateNormal];
    [btn5 addTarget:self action:@selector(postImage) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:btn5];
    //6.斷點續傳
}

#pragma mark - 上傳圖像
- (void)postImage
{
    //1.定義HttpClient
    NSURL *url = [NSURL URLWithString:@"地址"];
    AFHTTPClient *httpClient = [AFHTTPClient clientWithBaseURL:url]; //baseUrl後邊的請求都基於這個地址
    
    //2.根據HttpClient生成一個post請求
    NSMutableURLRequest *request = [httpClient multipartFormRequestWithMethod:@"POST" path:@"後續地址" parameters:nil constructingBodyWithBlock:^(id<AFMultipartFormData> formData) {
       //formData就是上傳的數據
        NSData *data = UIImagePNGRepresentation(_imageView.image);
        /**
         1.要上傳文件的參數
         2.負責上傳文件的遠處服務中接受文件使用的參數
         3.要上傳文件的文件名（別人告知）
         4.要上傳文件的文件類型（別人告知）
         */
        [formData appendPartWithFileData:data name:@"file" fileName:@"upload001.png" mimeType:@"image/png"];
    }];
    
    //3.準備作上傳的操做
    AFHTTPRequestOperation *op = [[AFHTTPRequestOperation alloc] initWithRequest:request];
    [op setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
        NSLog(@"上傳文件成功");
    } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
        NSLog(@"上傳文件失敗");
    }];
    
    [op start];
}

#pragma mark - 加載UIImageView
//若是異步在家表格圖像，不建議使用
- (void)loadImageView
{
    //1.建立一個UIImageView
    _imageView = [[UIImageView alloc] initWithFrame:CGRectMake(100, 0, 50, 50)];
    [self.view addSubview:_imageView];
    
    //2.URL
    NSURL *url = [NSURL URLWithString:@"圖片地址"];
    [_imageView setImageWithURL:url placeholderImage:[UIImage imageNamed:@""]];
}

#pragma mark - 加載XML
- (void)loadXML
{
    //1.URL
    NSURL *url = [NSURL URLWithString:@"地址"];
    
    //2.Request
    NSURLRequest *request = [NSURLRequest requestWithURL:url];
    
    //3.Connection（默認在主隊列，能夠新建一個隊列放入，不影響主界面）
    AFXMLRequestOperation *op = [AFXMLRequestOperation XMLParserRequestOperationWithRequest:request success:^(NSURLRequest *request, NSHTTPURLResponse *response, NSXMLParser *XMLParser) {
        NSLog(@"加載XML成功");
        
        //1.實例化解析器，並傳入數據 AFN已經作了 XMLParser
        //2.設置代理
        [XMLParser setDelegate:self];
        //3.解析器解析
        [XMLParser parse];
        
    } failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error, NSXMLParser *XMLParser) {
        NSLog(@"加載XML失敗");
    }];
    
    [_queue addOperation:op];
}
#pragma mark - XML解析器代理方法(6個)
- (void)parserDidEndDocument:(NSXMLParser *)parser
{
    
}

#pragma mark - 加載JSON
- (void)loadJSON
{
    //1.URL
    NSURL *url = [NSURL URLWithString:@"地址"];
    
    //2.Request
    NSURLRequest *request = [NSURLRequest requestWithURL:url];
    
    //3.Connection（默認在主隊列，能夠新建一個隊列放入，不影響主界面）
    AFJSONRequestOperation *op = [AFJSONRequestOperation JSONRequestOperationWithRequest:request success:^(NSURLRequest *request, NSHTTPURLResponse *response, id JSON) {
        NSLog(@"成功加載JSON");
    } failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error, id JSON) {
        NSLog(@"失敗加載JSON");
    }];
    
    [op start];
}

#pragma mark - 檢測鏈接狀態
- (void)reach
{
    //連接狀態的檢測
    NSURL *url = [NSURL URLWithString:@"http://www.baidu.com"];
    AFHTTPClient *httpClient = [AFHTTPClient clientWithBaseURL:url];
    
    [httpClient setReachabilityStatusChangeBlock:^(AFNetworkReachabilityStatus status) {
        switch (status) {
            case AFNetworkReachabilityStatusNotReachable:
                NSLog(@"無連接");
                break;
                
            case AFNetworkReachabilityStatusReachableViaWiFi:
                NSLog(@"Wifi");
                break;
                
            case AFNetworkReachabilityStatusReachableViaWWAN:
                NSLog(@"3G連接");
                break;
                
            default:
                NSLog(@"連接狀態未知");
                break;
        }
    }];
}

@end