使用QLPreviewController预览本地和网络文件

首先引入头文件

#import <QuickLook/QuickLook.h>

遵循代理

QLPreviewControllerDataSource

申明个QLPreviewController变量

@property (strong, nonatomic)QLPreviewController *previewController;

再声明一个NSUrl对象存放要返回的文件路径

@property (copy, nonatomic)NSURL *fileURL;

在viewDidLoad中初始化

- (void)viewDidLoad {
    [super viewDidLoad];
    self.previewController  =  [[QLPreviewController alloc]  init];
    self.previewController.dataSource  = self;
}

在预览本地文件的事件里面写下如下代码

//获取本地文件路径
    self.fileURL = [NSURL fileURLWithPath:[[NSBundle mainBundle]pathForResource:@"李碧华佳句赏析.doc" ofType:nil]];
    [self presentViewController:self.previewController animated:YES completion:nil];

遵循代理方法

#pragma mark - QLPreviewControllerDataSource
-(id<QLPreviewItem>)previewController:(QLPreviewController *)controller previewItemAtIndex:(NSInteger)index {
    return self.fileURL;
}
 
- (NSInteger)numberOfPreviewItemsInPreviewController:(QLPreviewController *)previewController{
    return 1;
}

这样本地文件的预览就成了

添加文件到项目的时候要注意，将文件放到工程项目之后，还要到Build Phases的Copy Bundle Resources中将文件添加到资源库，不然使用的时候会找不到文件而崩溃

接下来是预览网络文件

在网络文件预览的事件里面写下如下代码(需要引入AFN)

NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration defaultSessionConfiguration];
    
    AFURLSessionManager *manager = [[AFURLSessionManager alloc] initWithSessionConfiguration:configuration];
    NSString *urlStr = @"https://www.tutorialspoint.com/ios/ios_tutorial.pdf";
    NSString *fileName = [urlStr lastPathComponent]; //获取文件名称
    NSURL *URL = [NSURL URLWithString:urlStr];
    NSURLRequest *request = [NSURLRequest requestWithURL:URL];
    
    //判断是否存在
    if([self isFileExist:fileName]) {
        NSURL *documentsDirectoryURL = [[NSFileManager defaultManager] URLForDirectory:NSDocumentDirectory inDomain:NSUserDomainMask appropriateForURL:nil create:NO error:nil];
        NSURL *url = [documentsDirectoryURL URLByAppendingPathComponent:fileName];
        self.fileURL = url;
        [self presentViewController:self.previewController animated:YES completion:nil];
    }else {
        [SVProgressHUD showWithStatus:@"下载中"];
        NSURLSessionDownloadTask *downloadTask = [manager downloadTaskWithRequest:request progress:^(NSProgress *downloadProgress){
            
        } destination:^NSURL *(NSURL *targetPath, NSURLResponse *response) {
            NSURL *documentsDirectoryURL = [[NSFileManager defaultManager] URLForDirectory:NSDocumentDirectory inDomain:NSUserDomainMask appropriateForURL:nil create:NO error:nil];
            NSURL *url = [documentsDirectoryURL URLByAppendingPathComponent:fileName];
            return url;
        } completionHandler:^(NSURLResponse *response, NSURL *filePath, NSError *error) {
            [SVProgressHUD dismiss];
            self.fileURL = filePath;
            [self presentViewController:self.previewController animated:YES completion:nil];
        }];
        [downloadTask resume];
}

添加文件是否存在判断方法

//判断文件是否已经在沙盒中存在
-(BOOL) isFileExist:(NSString *)fileName
{
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *path = [paths objectAtIndex:0];
    NSString *filePath = [path stringByAppendingPathComponent:fileName];
    NSFileManager *fileManager = [NSFileManager defaultManager];
    BOOL result = [fileManager fileExistsAtPath:filePath];
    return result;
}

转载：https://blog.csdn.net/crypond/article/details/78130512