iOS 得到当前时间之前和之后N天的日期
NSInteger dis = 3; //前后的天数
NSDate*nowDate = [NSDate date];
NSDate* theDate;
if(dis!=0)
{
NSTimeInterval oneDay = 24*60*60*1; //1天的长度
theDate = [nowDate initWithTimeIntervalSinceNow: +oneDay*dis ];
//or
theDate = [nowDate initWithTimeIntervalSinceNow: -oneDay*dis ];
}
else
{
theDate = nowDate;
}
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关键就是这句了：theDate = [nowDate initWithTimeIntervalSinceNow:+oneDay*dis ];