Append TimeStamp to a File Name

Question

I have come across this problem several times in which I would like to have multiple versions of the same file in the same directory. The way I have been doing it using C# is by adding a time stamp to the file name with something like this DateTime.Now.ToString().Replace('/', '-').Replace(':', '.'). Is there a better way to do this?

Solution 1

You can use DateTime.ToString Method (String)

DateTime.Now.ToString("yyyyMMddHHmmssfff")

or string.Format

string.Format("{0:yyyy-MM-dd_HH-mm-ss-fff}", DateTime.Now);

or Interpolated Strings

$"{DateTime.Now:yyyy-MM-dd_HH-mm-ss-fff}"

There are following custom format specifiers y (year), M (month), d (day), h (hour 12), H (hour 24), m (minute), s (second), f (second fraction), F (second fraction, trailing zeroes are trimmed), t (P.M or A.M) and z (time zone).

With Extension Method

Usage:

string result = "myfile.txt".AppendTimeStamp();
//myfile20130604234625642.txt

Extension method

public static class MyExtensions
{
    public static string AppendTimeStamp(this string fileName)
    {
        return string.Concat(
            Path.GetFileNameWithoutExtension(fileName),
            DateTime.Now.ToString("yyyyMMddHHmmssfff"),
            Path.GetExtension(fileName)
            );
    }
}

Solution 2

I prefer to use:

string result = "myFile_" + DateTime.Now.ToFileTime() + ".txt";

What does ToFileTime() do?

Converts the value of the current DateTime object to a Windows file time.

public long ToFileTime()

A Windows file time is a 64-bit value that represents the number of 100-nanosecond intervals that have elapsed since 12:00 midnight, January 1, 1601 A.D. (C.E.) Coordinated Universal Time (UTC). Windows uses a file time to record when an application creates, accesses, or writes to a file.

Source: MSDN documentation - DateTime.ToFileTime Method

Solution 3

Perhaps appending DateTime.Now.Ticks instead, is a tiny bit faster since you won't be creating 3 strings and the ticks value will always be unique also.

Solution 4

you can use:

Stopwatch.GetTimestamp();

Solution 5

You can use below instead:

DateTime.Now.Ticks

View more solutions

Comments

[gilu]

I've added Path.GetDirectoryName(fileName) to get the full path to the file. Then replaced string.Concat()with Path.Combine() the get the full filename.

[Joseph]

this answer the way you get the timestamp!. append it to a file using the Path class and string manipulation is not an issue at all. this only an alternative to DateTime.ToString Method (String) or string.Format("{0:yyyy-MM-dd_hh-mm-ss-tt}",DateTime.Now);