文件夹管理器

/* createDirectoryAtPath:withIntermediateDirectories:attributes:error: creates a directory at the specified path. If you pass ‘NO‘ for createIntermediates, the directory must not exist at the time this call is made. Passing ‘YES‘ for ‘createIntermediates‘ will create any necessary intermediate directories. This method returns YES if all directories specified in ‘path‘ were created and attributes were set. Directories are created with attributes specified by the dictionary passed to ‘attributes‘. If no dictionary is supplied, directories are created according to the umask of the process. This method returns NO if a failure occurs at any stage of the operation. If an error parameter was provided, a presentable NSError will be returned by reference.
 
    This method replaces createDirectoryAtPath:attributes:
 */ 
// 参数1：创建的文件夹的路径
// 参数2：是否创建媒介的布尔值，一般为YES
// 参数3: 属性，没有就置为nil
// 参数4: 错误信息
- (BOOL)createDirectoryAtPath:(NSString *)path withIntermediateDirectories:(BOOL)createIntermediates attributes:(nullable NSDictionary<NSString *, id> *)attributes error:(NSError **)error NS_AVAILABLE(10_5, 2_0);

    // 创建对象
    NSFileManager *manager = [NSFileManager defaultManager];
    // 创建路径
    NSString *path = NSHomeDirectory();
    
    path = [path stringByAppendingPathComponent:@"test/myApp"];
    
    NSLog(@"%@", path);
    
    NSError *error = nil;
    
    // 创建文件夹
    BOOL success = [manager createDirectoryAtPath:path
                      withIntermediateDirectories:YES
                                       attributes:nil
                                            error:&error];
    NSLog(@"success = %d，error = %@", success,error);

// 参数1：要写入内容的文件的文件路径
// 参数2：一个BOOL值，一般为YES
// 参数3: 编码方式，一般为UTF8
// 参数4：错误信息
- (BOOL)writeToFile:(NSString *)path atomically:(BOOL)useAuxiliaryFile encoding:(NSStringEncoding)enc error:(NSError **)error;

    //向文件夹中添加字符串
    path = [path stringByAppendingPathComponent:@"zifucuan.txt"];
    
    //初始化一个字符串
    NSString *string = @"hello";
    
    BOOL success1 = [string writeToFile:path atomically:YES encoding:NSUTF8StringEncoding error:nil];
    
    if (success1) {
       
        NSLog(@"成功：%@",path);
    }else{
        NSLog(@"失败");
    }

// 参数1：路径
// 参数2：错误信息
- (BOOL)removeItemAtPath:(NSString *)path error:(NSError **)error NS_AVAILABLE(10_5, 2_0);

    // 删除path目录下的所有文件
    [manager removeItemAtPath:path error:nil];

// 参数1：要移动的文件路径
// 参数2：要移动到的文件路径（目的地）
// 参数3：错误信息
- (BOOL)moveItemAtPath:(NSString *)srcPath toPath:(NSString *)dstPath error:(NSError **)error NS_AVAILABLE(10_5, 2_0);

    NSString *documentPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
    
    // 创建一个文件夹
    NSString *copyPath = [documentPath stringByAppendingPathComponent:@"备份/test.txt"];
    
    // stringByDeletingLastPathComponent 删除最后一个路径
    [manager createDirectoryAtPath:[copyPath stringByDeletingLastPathComponent]
       withIntermediateDirectories:YES
                        attributes:nil
                             error:nil];
    // 定义一个字符串
    NSString *testStr = @"Hello World";
    
    NSData *data = [testStr dataUsingEncoding:NSUTF8StringEncoding];
    
    // 将内容写入文件
    [manager createFileAtPath:copyPath
                     contents:data
                   attributes:nil];
    
    // 创建一个toPath
    NSString *toPath = [documentPath stringByAppendingPathComponent:@"hello/copyTest.txt"];
    
    // 创建一个移动到的文件夹及文件
    [manager createDirectoryAtPath:[toPath stringByDeletingLastPathComponent]
       withIntermediateDirectories:YES
                        attributes:nil
                             error:nil];
    
    BOOL result = [manager moveItemAtPath:copyPath
                                   toPath:toPath
                                    error:nil];
    NSLog(@"result = %d", result);

// 参数1：要拷贝的文件路径 
// 参数2：要拷贝到的文件路径（目的地） 
// 参数3：错误信息
- (BOOL)copyItemAtPath:(NSString *)srcPath toPath:(NSString *)dstPath error:(NSError **)error NS_AVAILABLE(10_5, 2_0);

// 路径使用上面的路径
[manager copyItemAtPath:copyPath
                     toPath:toPath
                      error:nil];

// 参数为文件路径
+ (nullable instancetype)fileHandleForUpdatingAtPath:(NSString *)path;

// 搜索到文件内容的末尾
- (unsigned long long)seekToEndOfFile;

    // 创建handle对象
    NSFileHandle *fileHandle = [NSFileHandle fileHandleForUpdatingAtPath:path];
    
    // 搜索到文本内容末尾
    [fileHandle seekToEndOfFile];
    
    NSString *appendStr = @"我是后来的";
    
    NSData *appendData = [appendStr dataUsingEncoding:NSUTF8StringEncoding];
    
    // 将数据写入到对接起
    [fileHandle writeData:appendData];
    
    // 关闭对接起
    [fileHandle closeFile];

// 参数为文件路径
+ (nullable instancetype)fileHandleForReadingAtPath:(NSString *)path;

@property (readonly, copy) NSData *availableData;

// 参数为一个和文件长度有关的数值
- (void)seekToFileOffset:(unsigned long long)offset;

- (NSData *)readDataToEndOfFile;

    // 将“123456”写入file2.txt文件夹中
    NSString * content = @"123456";
    NSString * filePath2 = [documentPath stringByAppendingPathComponent:@"file2.txt"];
    [fileManager createFileAtPath:filePath2 contents:[content dataUsingEncoding:NSUTF8StringEncoding] attributes:nil];
    
    // 通过fileHandle读取
    fileHandle = [NSFileHandle fileHandleForReadingAtPath:filePath2];
    // 获取数据长度
    NSUInteger length = [[fileHandle availableData] length];
    // 设置文件的偏移量为文件的一半
    [fileHandle seekToFileOffset:length/2.0];
    // 从文件的偏移量位置读取到最后
    NSData * data = [fileHandle readDataToEndOfFile];
    [fileHandle closeFile];
    // 打印读取的字符串
    NSString * string = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
    NSLog(@"%@",string);