NSString to NSDate is NOT working when called multiple times - objective-c

Question

I have written this function in a class:
- (NSDate *) convertDate : (NSString *) dateStr{
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:#"dd-MM-yyyy"];
[dateFormatter setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:0]];
NSDate *dateFrmStr = [[NSDate alloc] init];
dateFrmStr = [dateFormatter dateFromString:dateStr];
return dateFrmStr;
}
I am calling this function in another class like this:
NSString * dateStr1 =#"01-01-1977";
NSString * dateStr2 =#"22-12-1977";
NSString * dateStr3 =#"19-01-1978";
MyClass *data = [[MyClass alloc]init];
NSDate *dateObj1 = [data convertDate:dateStr1];
NSDate *dateObj2 = [data convertDate:dateStr2];
NSDate *dateObj3 = [data convertDate:dateStr3];
NSLog(#" >>> dateObj1 %#",dateObj1);
NSLog(#" >>> dateObj2 %#",dateObj2);
NSLog(#" >>> dateObj3 %#",dateObj3);
When I run this the only first date seems to get converted because the output I get is :
>>> dateObj1 1977-01-01 00:00:00 +0000
There is no error nothing but the programs just stops.

Answer 1

I've tried you're code and for me works very fine( with ARC ), probably you're issue is somewhere else in "MyClass"…
BTW! Why don't you make a "category" on NSDate?
Something like this :
NSDate + ConvertDate.h
#interface NSDate (ConvertDate)
+(NSDate *) convertDateFromString : (NSString *)dateString;
#end
NSDate + ConvertDate.m
#implementation NSDate (ConvertDate)
+(NSDate *)convertDateFromString:(NSString *)dateString{
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:#"dd-MM-yyyy"];
[dateFormatter setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:0]];
return [dateFormatter dateFromString:dateString];
}
#end
Yes it looks like your code, the only differences are that you don't need to allocate an instance of "MyClass" to use the
"convertDateFromString" method because you're using a class method.'

Answer 2

could it be
NSString * dateStr2 =#"22-12-1977";
that NSDate thinks 22 as the month??? maybe try 12-22-1977 instead?? i usually use NSDateFormatter to convert to string or date..