我正在尝试获取用户的应用程序支持文件夹的 NSString。
我知道我可以做到
NSString *path = @"~/Library/Application Support";
但这看起来不太优雅。我尝试过使用 NSSearchPathForDirectoriesInDomains
但它似乎很冗长并且创建了几个不必要的对象(至少,我的实现确实如此)。
有没有简单的方法可以做到这一点?
这已经过时了,对于当前的最佳实践,请使用
FileManager.default.urls(for:in:)
,如下面 @andyvn22 的评论所示。
最佳实践是将
NSSearchPathForDirectoriesInDomains
与 NSApplicationSupportDirectory
一起使用,尽可能“啰嗦”。
示例:
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSApplicationSupportDirectory, NSUserDomainMask, YES);
NSString *applicationSupportDirectory = [paths firstObject];
NSLog(@"applicationSupportDirectory: '%@'", applicationSupportDirectory);
NSLog 输出:
applicationSupportDirectory: '/Volumes/User/me/Library/Application Support'
斯威夫特:
print(NSHomeDirectory())
或
print(FileManager.default.urls(for: .applicationSupportDirectory, in: .userDomainMask).first)
和
let yourString = String(FileManager.default.urls(for: .applicationSupportDirectory, in: .userDomainMask).first)
斯威夫特3:
FileManager.default.urls(for: .applicationSupportDirectory, in: .userDomainMask).first
只是为了确保人们会开始使用推荐的方法来执行此操作:
- (NSArray<NSURL *> * _Nonnull)URLsForDirectory:(NSSearchPathDirectory)directory
inDomains:(NSSearchPathDomainMask)domainMask
文档中的扩展示例:
- (NSURL*)applicationDataDirectory {
NSFileManager* sharedFM = [NSFileManager defaultManager];
NSArray* possibleURLs = [sharedFM URLsForDirectory:NSApplicationSupportDirectory
inDomains:NSUserDomainMask];
NSURL* appSupportDir = nil;
NSURL* appDirectory = nil;
if ([possibleURLs count] >= 1) {
// Use the first directory (if multiple are returned)
appSupportDir = [possibleURLs objectAtIndex:0];
}
// If a valid app support directory exists, add the
// app's bundle ID to it to specify the final directory.
if (appSupportDir) {
NSString* appBundleID = [[NSBundle mainBundle] bundleIdentifier];
appDirectory = [appSupportDir URLByAppendingPathComponent:appBundleID];
}
return appDirectory;
}
这对我有用:
NSError *error;
NSURL* appSupportDir = [[NSFileManager defaultManager]
URLForDirectory:NSApplicationSupportDirectory
inDomain:NSUserDomainMask
appropriateForURL:nil
create:YES
error:&error];
iOS 16 更新:
URL.applicationSupportDirectory
,他们还为 documentsDirectory
添加了静态属性
创建单独的目标 C 类,用于读取和写入文档目录。我将避免重写代码。以下是我的版本。
//Directory.h
#import <Foundation/Foundation.h>
#import <UIKit/UIKit.h>
#define PATH (NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES))
#define BASEPATH (([PATH count] > 0)? [PATH objectAtIndex:0] : nil)
@interface DocumentsDirectory : NSObject
//Here you can also use URL path as return type and file path.
+(void)removeFilesfromDocumentsDirectory:(NSString*)filename;
+(NSString*)writeFiletoDocumentsDirectory:(NSString*)filename;
@end
#import "Directory.h"
@implementation DocumentsDirectory
UIAlertView *updateAlert;
+(void)removeFilesfromDocumentsDirectory:(NSString*)filename
{
NSFileManager *fileManager = [NSFileManager defaultManager];
NSString *filePath = [BASEPATH stringByAppendingPathComponent:filename];
NSError *error;
BOOL success = [fileManager removeItemAtPath:filePath error:&error]; //Remove or delete file from documents directory.
if (success)
{
updateAlert= [[UIAlertView alloc] initWithTitle:@"Congratulations:" message:@"File is updated successfully" delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil];
[updateAlert show];
}
else
{
NSLog(@"Could not delete file -:%@ ",[error localizedDescription]);
updateAlert= [[UIAlertView alloc] initWithTitle:@"Try again:" message:[error localizedDescription] delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil];
[updateAlert show];
}
}
+(NSString*)writeFiletoDocumentsDirectory:(NSString*)filename
{
NSString *foldDestination = BASEPATH;
NSString *filePath = [foldDestination stringByAppendingPathComponent:filename];
return filePath;
}
@end
这就是我用来获取数据库的。从斯坦福大学课堂上得到的。它可能对某人有帮助。
NSURL *url = [[[NSFileManager URLsForDirectory:NSApplicationSupportDirectory inDomains:NSUserDomainMask] lastObject];
url = [url URLByAppendingPathComponent:@"database_name"];
NSLog(@"Database URL: %@",url);