NSDocumentDirectory与NSDocumentationDirectory 的区别：
NSDocumentDirectory是指程序中对应的Documents路径，而NSDocumentionDirectory对应于程序中的Library/Documentation路径，这个路径是没有读写权限的，所以看不到文件生成。
获取写入路径：
- (NSString *)documentsDirectory {
NSString *documentsDirectory = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES).firstObject;
return documentsDirectory;
}
写入一
- (IBAction)write:(id)sender {
NSString *txt = @"This is a book";
NSString *filePath = [[self documentsDirectory] stringByAppendingPathComponent:@"MZString.txt"];
BOOL isSuccess = [txt writeToFile:filePath atomically:YES encoding:NSUTF8StringEncoding error:nil];
if (isSuccess) {
NSLog(@"Write Succeed");
} else {
NSLog(@"Write Failed");
}
// 追加写入（不覆盖原先数据)
NSFileHandle *handle = [NSFileHandle fileHandleForWritingAtPath:filePath];
[handle seekToEndOfFile]; // 移动到文件的末尾
[handle writeData:[@"以下为追加写入😄" dataUsingEncoding:NSUTF8StringEncoding]]; // 在文件末尾写入数据
[handle closeFile]; // 关闭
NSLog(@"%@", filePath);
// 获取文件总长度
NSFileManager *manager = [NSFileManager defaultManager];
NSDictionary *dict = [manager attributesOfItemAtPath:filePath error:nil]; // 返回给定路径item的属性
long long length = [[dict objectForKey:NSFileSize] longLongValue];
NSLog(@"%lld", length);
}
// 沙盒路径
- (NSString *)documentsDirectory {
NSString *documentsDirectory = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES).firstObject;
return documentsDirectory;
}
写入二
- (IBAction)write:(id)sender {
NSLog(@"%@", [self folderPath]);
// 检查缓存是否存在
NSString *filePath = [[self folderPath] stringByAppendingPathComponent:@"File"];
id contents = [self getContentsAtPath:filePath];
if (contents) {
NSLog(@"😄缓存存在：%@", contents);
return;
}
NSString *txt = @"{\"data\":\"This is a book.\"}";
[[NSFileManager defaultManager] createDirectoryAtPath:[self folderPath] withIntermediateDirectories:YES attributes:nil error:nil];
// 写入的速度比较慢
// [[NSFileManager defaultManager] createFileAtPath:filePath contents:[txt dataUsingEncoding:NSUTF8StringEncoding] attributes:nil];
[txt writeToFile:filePath atomically:YES encoding:NSUTF8StringEncoding error:nil];
}
// 沙盒路径
- (NSString *)documentsDirectory {
NSString *documentsDirectory = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES).firstObject;
return documentsDirectory;
}
// 存储路径
- (NSString *)folderPath {
return [[self documentsDirectory] stringByAppendingPathComponent:@"MyCache"];
}
// 检查缓存是否存在
- (id)getContentsAtPath:(NSString *)path {
// 指定路径不存在
if ([path isKindOfClass:[NSNull class]] || !path || path.length == 0) {
return nil;
}
NSData *data = [NSData dataWithContentsOfFile:path];
if (data) {
return [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableContainers|NSJSONReadingMutableLeaves error:nil];
}
return nil;
}
移动
- (IBAction)move:(id)sender {
NSString *filePath = [[self folderPath] stringByAppendingPathComponent:@"File"];
NSString *contFilePath = [[self folderPath] stringByAppendingPathComponent:@"newFile"];
NSFileManager *manager = [NSFileManager defaultManager];
[manager moveItemAtPath:filePath toPath:contFilePath error:nil];
}
复制
- (IBAction)copy:(id)sender {
NSString *filePath = [[self folderPath] stringByAppendingPathComponent:@"newFile"];
NSString *CopyFilePath = [[self folderPath] stringByAppendingPathComponent:@"CopedFile"];
NSFileManager *manager = [NSFileManager defaultManager];
[manager copyItemAtPath:filePath toPath:CopyFilePath error:nil];
}
删除
- (IBAction)delete:(id)sender {
NSString *file = [[self folderPath] stringByAppendingPathComponent:@"CopedFile"];
NSFileManager *manager = [NSFileManager defaultManager];
[manager removeItemAtPath:file error:nil];
}
