NSTimeInterval time = ([[NSDate date] timeIntervalSince1970]); //double
long digits = (long)time; //first 10 digits        
int decimalDigits = (int)(fmod(time, 1) * 1000); //3 missing digits
/*** long ***/
long timestamp = (digits * 1000) + decimalDigits;
/*** string ***/
NSString *timestampString = [NSString stringWithFormat:@"%ld%03d",digits ,decimalDigits];

试试这个:

NSDate * timestamp = [NSDate dateWithTimeIntervalSince1970:[[NSDate date] timeIntervalSince1970]];

NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:@"YYYY-MM-dd HH:mm:ss.SSS"];

NSString *newDateString = [dateFormatter stringFromDate:timestamp];
timestamp = (NSDate*)newDateString;

在本例中，dateWithTimeIntervalSince1970与格式化程序@"YYYY-MM-dd HH:mm:ss结合使用。它将返回带有年、月、日的日期和带有小时、分钟、秒和毫秒的时间。参见示例:"2015-12-02 04:43:15.008"。我使用NSString来确保格式之前已经写过。

// Timestamp after converting to milliseconds.

NSString * timeInMS = [NSString stringWithFormat:@"%lld", [@(floor([date timeIntervalSince1970] * 1000)) longLongValue]];

获取当前日期的毫秒数。

斯威夫特4 +:

func currentTimeInMilliSeconds()-> Int
    {
        let currentDate = Date()
        let since1970 = currentDate.timeIntervalSince1970
        return Int(since1970 * 1000)
    }

这是我给斯威夫特用的

var date = NSDate()
let currentTime = Int64(date.timeIntervalSince1970 * 1000)

print("Time in milliseconds is \(currentTime)")

使用本网站验证准确性http://currentmillis.com/

NSTimeInterval time = ([[NSDate date] timeIntervalSince1970]); //double
long digits = (long)time; //first 10 digits        
int decimalDigits = (int)(fmod(time, 1) * 1000); //3 missing digits
/*** long ***/
long timestamp = (digits * 1000) + decimalDigits;
/*** string ***/
NSString *timestampString = [NSString stringWithFormat:@"%ld%03d",digits ,decimalDigits];