文件夹大小不对

Question

此代码正确，但文件夹大小错误。如果我更改目录，大小总是错误的。例如，“%@/Caches/com.apple.Safari/Webpage Previews”的大小是 23 MB，但我有 16.5 KB。

NSString *path = [NSString stringWithFormat:@"%@/Caches/com.apple.Safari/Webpage Previews", [NSSearchPathForDirectoriesInDomains(NSLibraryDirectory, NSUserDomainMask, YES) objectAtIndex:0]];
    NSNumber *fileSize = [[[NSFileManager defaultManager] attributesOfItemAtPath:path error:nil] objectForKey:NSFileSize];
    resultsize += [fileSize unsignedLongLongValue];

我也用过这个，但大小总是错误的：

NSFileManager *fm = [[NSFileManager alloc] init];    
    NSURL *LibraryURL = [[fm URLsForDirectory:NSLibraryDirectory inDomains:NSUserDomainMask] lastObject];
    NSURL *previewsURL = [LibraryURL URLByAppendingPathComponent:@"Caches/com.apple.Safari/Webpage Previews"];

    resultSize += [[[fm attributesOfItemAtPath:[previewsURL path] error:nil] objectForKey:NSFileSize] unsignedIntegerValue];

你能帮助我吗？谢谢。

Answer 1

如果要获取文件夹中所有文件的大小，则需要遍历文件夹的内容并获取实际文件的大小：

unsigned long long totalSize = 0;
NSFileManager *fm = [[NSFileManager alloc] init];
NSURL *libraryURL = [[fm URLsForDirectory:NSLibraryDirectory inDomains:NSUserDomainMask] lastObject];
NSURL *previewsURL = [LibraryURL URLByAppendingPathComponent:@"Caches/com.apple.Safari/Webpage Previews"];

NSDirectoryEnumerator *enumerator = [fm enumeratorAtURL:previewsURL includingPropertiesForKeys:[NSArray arrayWithObject:NSURLFileSizeKey] options:0 errorHandler:nil /* or an actual error handler */];

for (NSURL *url in enumerator) {
    NSNumber *sizeNumber;
    if ([url getResourceValue:&sizeNumber forKey:NSURLFileSizeKey error:nil /* or an error */])
        totalSize += [sizeNumber unsignedLongLongValue]; 
}

（我没有测试过这个。）