How to save unique image name in document directory

Question

In my ios app i am stuck on a task. I need to take pic from camera and save it on document directory.Problem is that i want save unique name of image.I was try to add current time with a name. but there are length problem to save image.Please suggest me how can i do that task.

Thanks

Answer 1

Given a proposed name like NString *name = @"Lake" :

NSString *myUniqueName = [NSString stringWithFormat:@"%@-%u", name, (NSUInteger)([[NSDate date] timeIntervalSince1970]*10.0)];

EDIT: updated so that the only chance of a duplicate is the same original name, submitted within 100 ms of the first (virtually impossible in my opinion, if this is a concern use 100 instead of 10)

Answer 2

-(NSString*)getFilePathToSaveUnUpdatedImage
{
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *directory = [paths objectAtIndex:0];

    for (int i = 0 ; TRUE ; i++)
    {
        if(![[NSFileManager defaultManager]fileExistsAtPath:[NSString stringWithFormat:@"%@/UnUpdatedItems/Image%d.png", directory , i]])
            return [NSString stringWithFormat:@"%@/UnUpdatedItems/Image%d.png", directory , i];
    }
}

Answer 3

Try like this just formate the date and save the image

NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init];

[dateFormat setDateFormat:@"yyyy-MM-dd HH:mm:ss"];

NSDate *now = [NSDate date];

NSString *theDate = [dateFormat stringFromDate:now];

[data writeToFile:[NSString stringWithFormat:@"%@.png",theDate] atomically:YES];

Answer 4

use this line of code to give name.

[NSDateFormatter localizedStringFromDate:[NSDate date] dateStyle:NSDateFormatterMediumStyle timeStyle:NSDateFormatterShortStyle]]

This works for me for same problem.

Answer 5

-(NSString*)getImagePathName
{
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *directory = [paths objectAtIndex:0];

    for (int i = 0 ; TRUE ; i++)
    {
        if(![[NSFileManager defaultManager]fileExistsAtPath:[NSString stringWithFormat:@"%@/Image%d.png", directory , i]])
            return [NSString stringWithFormat:@"%@/Image%d.png", directory , i];
    }
}