iOS OC开发，文件的下载、预览

/// 下载/打开

- (void)downloadActionWithDownloadString:(NSString *)downloadString{

//url : 下载地址

NSString *url;

if ([downloadString containsString:@"?"]) {

NSRange range = [downloadString rangeOfString:@"?"];

url = [downloadString substringToIndex:range.location];

}else{

url = downloadString;

}

//suffix : 后缀.zip .doc

NSString * suffix = [url pathExtension];

NSMutableArray *tempArray = [NSMutableArray arrayWithArray:[url  componentsSeparatedByCharactersInSet:[NSCharacterSet characterSetWithCharactersInString:@"/."]]];//@",!"以,或!切割，而不是把,!连在一起当成一个整体进行切割

NSInteger count = tempArray.count-2;

NSString *preName = tempArray[count];

//name : 文件名XXX.zip

NSString * name = [NSString stringWithFormat:@"%@.%@", preName,suffix];

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);

NSString *documentsDirectory = [paths lastObject];

NSFileManager *fileManager = [NSFileManager defaultManager];

//创建一个本地沙盒文件,便于日后管理,比如删除

NSString * filesPath = [documentsDirectory stringByAppendingPathComponent:@"files"];

if (![[NSFileManager defaultManager] fileExistsAtPath:filesPath]) {

/// 创建一个文件

BOOL success =  [[NSFileManager defaultManager] createDirectoryAtPath:filesPath withIntermediateDirectories:YES attributes:nil error:nil];

NSLog(@"success:%d", success);

}

//filepath :下载后的文件本地路径

NSString *filePath = [filesPath stringByAppendingPathComponent:[NSString stringWithFormat:@"/%@", name]];

if ([fileManager fileExistsAtPath:filePath]) {

//文件已经存在,直接打开

UIAlertController * alertController = [UIAlertController alertControllerWithTitle:@"是否打开文件" message:nil preferredStyle:UIAlertControllerStyleAlert];

UIAlertAction * cancelAction  =[UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:nil];

[alertController addAction:cancelAction];

[alertController addAction:[UIAlertAction actionWithTitle:@"确定" style:UIAlertActionStyleDestructive handler:^(UIAlertAction * _Nonnull action) {

[self openDocxWithPath:filePath];

}]];

[self presentViewController:alertController animated:YES completion:nil];

}else {

//文件不存在,要下载

UIAlertController * alertController = [UIAlertController alertControllerWithTitle:@"是否下载并打开文件" message:nil preferredStyle:UIAlertControllerStyleAlert];

UIAlertAction * cancelAction  =[UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:nil];

[alertController addAction:cancelAction];

[alertController addAction:[UIAlertAction actionWithTitle:@"确定" style:UIAlertActionStyleDestructive handler:^(UIAlertAction * _Nonnull action) {

[self downloadDocxWithFilePath:filePath downloadString:downloadString];

}]];

[self presentViewController:alertController animated:YES completion:nil];

}

}

/**

下载文件

@param filePath 文件本地路径

@param downloadString 文件下载地址

*/

-(void)downloadDocxWithFilePath:(NSString *)filePath downloadString:(NSString *)downloadString{

NSString *urlString = downloadString;

NSURL * url = [NSURL URLWithString:urlString];

NSURLRequest *request = [NSURLRequest requestWithURL:url];

AFHTTPSessionManager *manager = [AFHTTPSessionManager manager];

NSURLSessionDownloadTask *task = [manager downloadTaskWithRequest:request progress:^(NSProgress * _Nonnull downloadProgress) {

NSLog(@"%lld   %lld",downloadProgress.completedUnitCount,downloadProgress.totalUnitCount);

NSLog(@"下载中....");

} destination:^NSURL * _Nonnull(NSURL * _Nonnull targetPath, NSURLResponse * _Nonnull response) {

return [NSURL fileURLWithPath:filePath];  //这里返回的是文件下载到哪里的路径 要注意的是必须是携带协议file://

} completionHandler:^(NSURLResponse * _Nonnull response, NSURL * _Nullable filePath, NSError * _Nullable error) {

NSString *name = [filePath path];

[self openDocxWithPath:name];

}];

[task resume];

}

/**

打开文件

@param filePath 文件路径

*/

-(void)openDocxWithPath:(NSString *)filePath {

UIDocumentInteractionController *doc= [UIDocumentInteractionController interactionControllerWithURL:[NSURL fileURLWithPath:filePath]];

doc.delegate = self;

[doc presentPreviewAnimated:YES];

// 打开的过程有点慢

}

#pragma mark - UIDocumentInteractionControllerDelegate

//必须实现的代理方法 预览窗口以模式窗口的形式显示，因此需要在该方法中返回一个view controller ，作为预览窗口的父窗口。如果你不实现该方法，或者在该方法中返回 nil，或者你返回的 view controller 无法呈现模式窗口，则该预览窗口不会显示。

- (UIViewController *)documentInteractionControllerViewControllerForPreview:(UIDocumentInteractionController *)controller{

return self;

}

- (UIView*)documentInteractionControllerViewForPreview:(UIDocumentInteractionController*)controller {

return self.view;

}

- (CGRect)documentInteractionControllerRectForPreview:(UIDocumentInteractionController*)controller {

return CGRectMake(0, 30, self.view.frame.size.width, self.view.frame.size.height);

}