removeItemAtPath 在设备上不起作用

Posted 2023-03-07

【中文标题】removeItemAtPath 在设备上不起作用

【英文标题】：removeItemAtPath dosn't work on the device

【发布时间】：2010-09-01 13:16:51

【问题描述】：

我一直在努力解决这个问题，所以欢迎任何提示或建议。

我正在尝试从“文档”下的目录中删除文件。问题是该文件没有在设备上删除，而是在模拟器上。 更神秘的是，在调用 removeItemAtPath 之前，我使用 fileExistsAtPath 检查文件是否存在，甚至显示该文件夹下的文件列表。

附上删除代码：

// Override to support editing the table view.
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath 

if (editingStyle == UITableViewCellEditingStyleDelete) 

// Delete file
NSString *directory = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:@"Documents/MyDir"];
NSString *path = [directory stringByAppendingPathComponent:[mListOfItems objectAtIndex:indexPath.row]];
NSError *error = nil;

// Check if FileName doesn't exist.
NSFileManager *fileManager = [NSFileManager defaultManager];

if (![[NSFileManager defaultManager] fileExistsAtPath:path]) 
 UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"File Deletion Failed" message:[NSString stringWithFormat:@"File %@ not found.", [mListOfItems objectAtIndex:indexPath.row]]  delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil];
 [alertView show];
 [alertView release];   

else 

  FAILED HERE ---V  
        if (![fileManager removeItemAtPath:path error:&error]) 
UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"Error While Deleting File" message:[NSString stringWithFormat:@"%@", error]  delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil];
[alertView show];
[alertView release];   

 
 else 
// delete row from local data
[self.tableView beginUpdates];
[mListOfItems removeObjectAtIndex:indexPath.row];

// Delete the row from view
[tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationLeft];
[self.tableView endUpdates];
 // Delete - success
// File Exist
// Edit - Delete   

显示该文件夹中文件列表的代码...

   - (void) handleFilesRowTapped
 

 // Get list of files to be displayed
 NSFileManager *manager = [NSFileManager defaultManager];
   NSError *error = nil;
 NSString * directory = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:@"Documents/MyDir"];
 NSArray *fileList = [manager contentsOfDirectoryAtPath:directory error:&error];

 // Allocate file list view controller
 FileListViewController *fileListViewController = [[FileListViewController alloc] initWithNibName:@"FileListViewController" bundle:nil];

 //// Make sure that only *.TXT files are displayed

 // Set the list to be displayed
 fileListViewController.mListOfItems = [[NSMutableArray alloc] init];
 for (NSString *fileName in fileList) 
  if (([[fileName substringWithRange:NSMakeRange([fileName length] - 4, 4)]     compare:@".txt"] == NSOrderedSame) || 
 ([[fileName substringWithRange:NSMakeRange([fileName length] - 4, 4)] compare:@".TXT"] == NSOrderedSame))
   [fileListViewController.mListOfItems addObject:fileName];
  
 

 // Configure viwe controller
 [fileListViewController setTitle:@"Files"];

 // Push for display
 [self.navigationController pushViewController:fileListViewController animated:YES];
 [fileListViewController release];

    

非常感谢。

【问题讨论】：

错误对象返回了什么？

【参考方案1】：

这个：

[[NSBundle mainBundle] resourcePath]

... 返回如下路径：

~/Library/Application Support/iPhone Simulator/4.0.1/Applications/6FACD1C6-3E81-4FE1-97E0-F80604E134E0/i4TestBed.app

...这是应用程序包本身的路径，它是只读的。一旦应用程序被编译，它的包内容无论如何都不会改变。

要在文档文件夹中查找文件，请使用：

NSArray *docPaths=NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *docPath=[docPaths objectAtIndex:0];

... 返回如下路径：

~/Library/Application Support/iPhone Simulator/4.0.1/Applications/6FACD1C6-3E81-4FE1-97E0-F80604E134E0/Documents

附加文件名就可以了。