[英]Modify an existing file in directory, with ought replacing it (iPhone)
在我的應用程序中,每次用戶創建新組時,都會創建此代碼(JSON):
{"group a":"0864797073"}
...然后代碼保存在名為groups.txt的文件的目錄中
...但是當用戶創建另一個組時,我希望以這種方式修改文件:
{"group a":"0864797073"}
{"group b":"0864797073"}
...接着...
{"group a":"0864797073"}
{"group b":"0864797073"}
{"group c":"0864797073"}
...所以添加一個新行,而不是替換文件。
我怎樣才能做到這一點??
先謝謝您的幫助。
編輯2:
NSString * destDir = [NSString stringWithFormat:@“/ Apps / Quick Homework&business /%@ /”,namegroup.text];
NSString *filename5 = namegroup.text;
NSString *filename6 = @"group";
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *groupPath = [documentsDirectory stringByAppendingPathComponent:[NSString stringWithFormat:@"%@", filename6]];
NSMutableArray *titles = [NSMutableArray array];
[titles addObject:filename5];
NSMutableArray *keys = [NSMutableArray array];
[keys addObject:filename6];
NSDictionary *dict = [NSDictionary dictionaryWithObjects:titles forKeys:keys];
NSString *jsonString = [dict JSONRepresentation];
NSData *jsonData = [jsonString dataUsingEncoding: NSUTF8StringEncoding];
NSFileHandle *myHandle = [NSFileHandle fileHandleForUpdatingAtPath:groupPath];
[myHandle seekToEndOfFile];
[myHandle writeData:jsonData];
[myHandle closeFile];
[jsonData writeToFile: groupPath atomically: YES];
[[self restClient] uploadFile:filename6 toPath:destDir
withParentRev:nil fromPath:groupPath];
如果您只想在現有文件的末尾添加一行,則可以使用以下代碼。
NSData *newGroupData = [newGroupString dataUsingEncoding:NSUTF8StringEncoding];
NSFileHandle *myHandle = [NSFileHandle fileHandleForUpdatingAtPath:filePath];
[myHandle seekToEndOfFile];
[myHandle writeData:newGroupData];
[myHandle closeFile];
您可以newGroupString
設置newGroupString
和filePath
的值
您執行以下操作
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