学步园

#import <Foundation/Foundation.h>

@interface NSDate (StringAndDate)

//fromatter:@"yyyy-MM-dd HH:mm" ; stringDate:@"2012-03-01 23:12"
+ (NSDate *)getDateFromString:(NSString *)stringDate withFormatter:(NSString *)formatter;
+ (NSString *)getStringFromDate:(NSDate *)date withFormatter:(NSString *)formatter;

@end

#import "NSDate+StringAndDate.h"

@implementation NSDate (StringAndDate)

+ (NSDate *)getDateFromString:(NSString *)stringDate withFormatter:(NSString *)formatter
{
    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
    [dateFormatter setDateFormat:formatter];
    NSDate *date = [dateFormatter dateFromString:stringDate];
    [dateFormatter release];
    
    return date;
}
+ (NSString *)getStringFromDate:(NSDate *)date withFormatter:(NSString *)formatter
{
    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
    [dateFormatter setDateFormat:formatter];
    NSString *dayString = [dateFormatter stringFromDate:date];
    [dateFormatter release];
    
    return dayString;
}

@end

调用方法：

    NSDate *date1 = [NSDate getDateFromString:startStopTime withFormatter:@"yyyy-MM-dd,HH:mm"];

    NSString *dayString = [NSDate getStringFromDate:day withFormatter:@"yyyy-MM-dd"];