iOS - 下载文件

1.下载本地文件

将文件放入项目中（文件名不能为中文）

NSString *fileNameStr = @"Authorization";

    NSString *path = [[NSBundle mainBundle] pathForResource:fileNameStr ofType:@"doc"];

    NSString *encodedString = [path stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];


    NSURL *url = [NSURL fileURLWithPath:encodedString];

    NSArray *dataAry = @[url];
    UIActivityViewController *activityController=[[UIActivityViewController alloc]initWithActivityItems:dataAry applicationActivities:nil];
    [self.navigationController presentViewController:activityController animated:YES completion:nil];

2.通过接口下载文件（接口返回数据流）

返回数据示例：

WechatIMG1.jpeg

    NSString *nameStr = @"";//文件名

    NSString *strUrl =@"";//接口名

    AFHTTPSessionManager *manager = [AFHTTPSessionManager manager];
    manager.requestSerializer.timeoutInterval = 60;
    manager.requestSerializer = [AFHTTPRequestSerializer serializer];
    manager.responseSerializer = [AFHTTPResponseSerializer serializer];


    [manager GET:strUrl parameters:nil progress:nil success:^(NSURLSessionDataTask * _Nonnull task, id  _Nullable responseObject) {

        NSLog(@"%@",responseObject);

        // 获取数据流，写入本地
        [self writeToFile:responseObject fileName:nameStr];

    } failure:^(NSURLSessionDataTask * _Nullable task, NSError * _Nonnull error) {
        NSLog(@"%@",error);
    }];


// 写入文件
-(void)writeToFile:(NSData *)data fileName:(NSString *)fileName{


    NSArray* paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString * _filePath = [paths objectAtIndex:0];

    fileName = [NSString stringWithFormat:@"%@.doc",fileName];
    NSString * filePath = [_filePath stringByAppendingPathComponent:fileName];


    // NSData写入文件
    [data writeToFile:filePath atomically:YES];
    NSLog(@"fileDataPath is %@", filePath);


    NSString *encodedString = [filePath stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
    self.fileUrl = [NSURL fileURLWithPath:encodedString];

    UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"下载成功" message:@"是否保存文件？" delegate:self cancelButtonTitle:@"取消" otherButtonTitles:@"确定", nil];
    [alert show];


}




- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex NS_DEPRECATED_IOS(2_0, 9_0)
{
    if(buttonIndex == 1)
    {
        NSArray *dataAry = @[self.fileUrl];
        UIActivityViewController *activityController=[[UIActivityViewController alloc]initWithActivityItems:dataAry applicationActivities:nil];
        [self.navigationController presentViewController:activityController animated:YES completion:nil];
    }
}

3.通过接口下载文件（接口返回文件存储地址）

返回文件存储地址示例：http://gangquan-sit.oss-cn-beijing.aliyuncs.com/erp2.0/planorder/567e33094cda46369ec16bd1d852350c?Expires=1560915811&OSSAccessKeyId=LTAIOdSUxv9XSNHW&Signature=vebabOpx4/whg+7u2ZHL3pq9qE0=

需要导入工具类，链接: https://pan.baidu.com/s/1puLhN5rKpvS_cVY-iWWGUA 提取码: yyuj

#pragma mark - 下载文件
- (void)downloadFile:(NSString *)fileStr{

// fileStr即接口返回的链接
    [SVProgressHUD show];
    
    /*
     1. NSDocumentDirectory
     下载文件到该目录，则该文档可以用 iTunes 直接查看。对于安全性不高，便于浏览的文件，pdf ，可以考虑下载到该目录。、
     2. NSLibraryDirectory
     下载文件到该目录，则该文档不可用 iTunes 直接查看。只能在 APP 内部查看，对于文件有安全性方面的考虑，可以下载到该 目录。
     3.NSCachesDirectory
     该目录存放的主要是缓存文件，如 图片的缓存数据等。不适合存放永久性的文件。
     */


    //设置下载文件保存的目录
    NSArray* paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString* _filePath = [paths objectAtIndex:0];

    //Encode Url 如果Url 中含有空格，一定要先 Encode
    fileStr = [fileStr stringByReplacingOccurrencesOfString:@" " withString:@""];

    //创建 Request
    NSURLRequest* request = [NSURLRequest requestWithURL:[NSURL URLWithString:fileStr]];
    NSString* fileName = @"";//文件名
    NSString* filePath = [_filePath stringByAppendingPathComponent:fileName];

    //下载进行中的事件

    AFURLConnectionOperation *operation = [[AFHTTPRequestOperation alloc] initWithRequest:request];

    operation.outputStream = [NSOutputStream outputStreamToFileAtPath:filePath append:NO];


    [operation setDownloadProgressBlock:^(NSUInteger bytesRead,long long totalBytesRead,long long totalBytesExpectedToRead) {

        //下载的进度，如 0.53，就是 53%

        float progress = (float)totalBytesRead / totalBytesExpectedToRead;


    //下载完成的事件该方法会在下载完成后延迟 2秒左右执行 根据完成后需要处理的及时性不高，可以采用该方法

    [operation setCompletionBlock:^{

        [SVProgressHUD dismiss];
        self.filePath = filePath;

        UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"下载成功" message:@"是否预览文件？" delegate:self cancelButtonTitle:@"取消" otherButtonTitles:@"确定", nil];
        [alert show];

    }];

    [operation start];
}


- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex NS_DEPRECATED_IOS(2_0, 9_0)
{
    if(buttonIndex == 1)
    {
        NSLog(@"ok");
        ShowFileViewController *vc = [[ShowFileViewController alloc] init];
        vc.filePath = self.filePath;
        [[Singleton singleton].myViewController.navigationController pushViewController:vc animated:YES];

    }
}

预览文件

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.

    self.title = @"文件预览";

    [self.view addSubview:self.webView];

// 保存文件
    self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc] initWithImage:[UIImage imageNamed:@"组-1"] style:UIBarButtonItemStylePlain target:self action:@selector(saveAction)];

}

-(UIWebView *)webView
{
    if (!_webView) {
        _webView = [[UIWebView alloc] init];
        _webView.frame = CGRectMake(0,KNavHeight, self.view.frame.size.width, self.view.frame.size.height-KNavHeight);
        //UIDataDetectorTypes自动检测电话、网址和邮箱
        //禁止数字链接
        //_webView.dataDetectorTypes = UIDataDetectorTypeNone;
        _webView.delegate = self;
        _webView.backgroundColor = [UIColor clearColor];


        NSURL *url = [NSURL fileURLWithPath:self.filePath];
        _webView.scalesPageToFit = YES;
        NSURLRequest *request = [NSURLRequest requestWithURL:url];
        [self.webView loadRequest:request];

    }
    return _webView;

}


// 保存文件
- (void)saveAction{
    NSData *data = [NSData dataWithContentsOfFile:self.filePath];
    NSArray *ary = @[data];
    UIActivityViewController *activityController=[[UIActivityViewController alloc]initWithActivityItems:ary applicationActivities:nil];
    [self.navigationController presentViewController:activityController animated:YES completion:nil];
}