nsdata nstring int

int --> NSData
int someInt = 1;
NSString *aString = [NSString stringWithFormat:@"%d",someInt];
NSData *someData = [aString dataUsingEncoding:NSUTF8StringEncoding];
[someData writeToFile:[documentsDirectory stringByAppendingString:@"someFile"] atomically:YES];



NSData --> int

NSData* someData = [NSData dataWithContentsOfFile:[documentsDirectory stringByAppendingString:@"someFile"］;
NSString *aString = ［NSString alloc] initWithData:someData encoding:NSUTF8StringEncoding];
int someInt = [aString intValue];