我有一个由日期组成的数组,但是NSString
。我该如何排序下降?
编辑:我最后通过调整我的代码来使用NSDate,因为使用其他方法在我的情况下不起作用
答案 0 :(得分:10)
您可以使用sortedArrayUsingFunction
,请考虑以下示例
NSString *str1 = @"03-07-2012";
NSString *str2 = @"01-07-2012";
NSString *str3 = @"02-07-2012";
NSArray *arr = [NSArray arrayWithObjects:str1, str2, str3, nil];
arr = [arr sortedArrayUsingFunction:dateSort context:nil];
//The date sort function
NSComparisonResult dateSort(NSString *s1, NSString *s2, void *context) {
NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:@"dd-MM-yyyy"];
NSDate *d1 = [formatter dateFromString:s1];
NSDate *d2 = [formatter dateFromString:s2];
return [d1 compare:d2]; // ascending order
return [d2 compare:d1]; // descending order
}
答案 1 :(得分:2)
将NSString日期隐藏到NSDate对象,而不是基于日期排序数组
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setLocale:[[[NSLocale alloc] initWithLocaleIdentifier:@"en_US_POSIX"] autorelease]];
[dateFormatter setDateFormat:@"YYYY-MM-dd HH:mm:ss ZZZ"];
NSDate *date = [dateFormatter dateFromString:dateStr];
NSComparisonResult dateSort(NSString *s1, NSString *s2, void *context) {
NSDate *d1 = [NSDate dateWithString:s1];
NSDate *d2 = [NSDate dateWithString:s2];
return [d1 compare:d2];
}
NSArray *sorted = [unsorted sortedArrayUsingFunction:dateSort context:nil];