在iphone上的库目录中创建文件
我正在尝试在我的应用程序库目录的子目录中创建文件。首先,我得到了通向图书馆的路径,如下所示:在iphone上的库目录中创建文件,iphone,ios,nsfilemanager,Iphone,Ios,Nsfilemanager,我正在尝试在我的应用程序库目录的子目录中创建文件。首先,我得到了通向图书馆的路径,如下所示: - (NSURL*) getLibraryDirectory { NSFileManager* manager = [NSFileManager defaultManager]; NSArray* paths = [manager URLsForDirectory:NSLibraryDirectory inDomains:NSUserDomainMask]; if ([path
- (NSURL*) getLibraryDirectory
{
NSFileManager* manager = [NSFileManager defaultManager];
NSArray* paths = [manager URLsForDirectory:NSLibraryDirectory inDomains:NSUserDomainMask];
if ([paths count] > 0)
{
return [paths objectAtIndex:0];
}
return nil;
}
NSString* filePath = [[self getDirectory:DIR_COMMANDS] absoluteString];
if (filePath)
{
filePath = [filePath stringByAppendingPathComponent:@"test_file.tst"];
NSFileManager* manager = [NSFileManager defaultManager];
if ([manager createFileAtPath:filePath contents:[[NSData alloc] initWithBytes:[[@"string" dataUsingEncoding:NSUTF16LittleEndianStringEncoding] bytes] length:12] attributes:nil])
{
NSLog(@"YES");
}
else
{
NSLog(@"NO");
}
}
然后,我使用以下代码创建子文件夹:
- (NSURL*) getDirectory:(NSString*)subdirName
{
NSFileManager* sharedFM = [NSFileManager defaultManager];
NSURL* libraryDirectory = [self getLibraryDirectory];
if (libraryDirectory)
{
NSURL* subdir = [libraryDirectory URLByAppendingPathComponent:subdirName isDirectory:YES];
if (![sharedFM fileExistsAtPath:[subdir absoluteString] isDirectory:YES])
{
NSError* error;
if ([sharedFM createDirectoryAtURL:subdir withIntermediateDirectories:YES attributes:nil error:&error])
{
return subdir;
}
else
{
NSLog(@"Error occured while trying to create subdirectory \"%@\". Code - %d, desc - %@", subdirName, [error code], [error localizedDescription]);
}
}
}
return nil;
}
最后一件事是我试图在这个文件夹中创建一些文件,如下所示:
- (NSURL*) getLibraryDirectory
{
NSFileManager* manager = [NSFileManager defaultManager];
NSArray* paths = [manager URLsForDirectory:NSLibraryDirectory inDomains:NSUserDomainMask];
if ([paths count] > 0)
{
return [paths objectAtIndex:0];
}
return nil;
}
NSString* filePath = [[self getDirectory:DIR_COMMANDS] absoluteString];
if (filePath)
{
filePath = [filePath stringByAppendingPathComponent:@"test_file.tst"];
NSFileManager* manager = [NSFileManager defaultManager];
if ([manager createFileAtPath:filePath contents:[[NSData alloc] initWithBytes:[[@"string" dataUsingEncoding:NSUTF16LittleEndianStringEncoding] bytes] length:12] attributes:nil])
{
NSLog(@"YES");
}
else
{
NSLog(@"NO");
}
}
但不幸的是,我每次都得到“否”,我不明白为什么。要从文件URL获取路径,您必须使用
path
而不是absoluteString
NSString *filePath = [[self getDirectory:DIR_COMMANDS] path];
旁注:对于方法,您应该采用Cocoa的命名风格:libraryDirectory
,而不是getLibraryDirectory
,或者更好:libraryDirectoryURL
。只有通过引用传递返回值时,才会使用get
前缀
另外:您对fileExistsAtPath:isDirectory:
的使用不正确。BOOL
参数通过引用传递:
BOOL isDir;
if ([sharedFM fileExistsAtPath:[subdir path] isDirectory:&isDir]) {
if (! isDir) {
NSLog(@"There's a plain file at my path");
return nil;
}
}
在
NSLog(@“NO”)之前添加此行
查看有关创建文件路径失败原因的详细错误消息:失败:NSLog(@“错误为%s”,strerror(errno))代码>谢谢你,尼古拉!最后,它是有效的,而且你所有的评论都非常有用。我会仔细阅读文档。