Use DateTime.ToFileTime and FromFileTime through file name string

Question

I want to save to a specific space a single file at several states. So i thought about stamping it with the time of creation to tell one from another.

I have created a dummy program that goes through exactly the same procedure my full program does but concentrated.

Here is the code:

 DateTime first = DateTime.Now;
        long ft = first.ToFileTime();
        string time = "" + ft;
        long timeLong = Convert.ToInt64(time);

        DateTime normalDate = DateTime.FromFileTime(timeLong);
        string normalName = ""+ normalDate;
        DateTime thisDate = DateTime.Parse(normalName);

        long fit = thisDate.ToFileTime();

So it goes through those steps:

Create time and convert to long for file.
Save it as string inside the files name(i pass it like that but in "" is the files name)
Then i retrieve it, i cast it into long, to create a DateTime format readable for the human with FromFileTime.Then to string fro the user to read it in a comboBox.
Then the user selects and it becomes DateTime , to get into long through tge TiFileTime ( at this point i have the problem as it appears to loose everything smaller than seconds)

I want to cast it back into long at the end to be able to run through the files again and find the one that matches with the one that the user choose.

here is some output values:

Edit : As you can see form the results above. I miss something . The initial and the final values are not the same.So i cant find the same file again.

Not clear what the question is... can you be more specific about what you're missing? — Amittai Shapira, Dec 19 '17 at 18:48
It doesn't work. As the image shows my initial and my final results are not the same! — Feronimus, Dec 19 '17 at 18:50
I want to get the time from ToFileTime, into a string , then from FromFileTime into string again , and back into the orginal ToFileTime format... If you read the code , its not unclear. Its just complicated. — Feronimus, Dec 19 '17 at 18:58

Amittai Shapira · Accepted Answer · 2017-12-19T19:07:39.007

0

The Parse() method don't have all the information that the DateTime structure holds (you can find its members here).

string normalName = ""+ normalDate;
DateTime thisDate = DateTime.Parse(normalName);

Will not return the exact value (including Ticks) as the original one. You should do it as follows, using Ticks:

string normalName = "" + normalDate.Ticks;
DateTime thisDate = new DateTime(long.Parse(normalName));
long fit = thisDate.ToFileTime();

edited Dec 19 '17 at 19:07

answered Dec 19 '17 at 18:59

Amittai Shapira

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I see... So how i could take the time back into string (or long thought "ToFileTime") if i cant parse it? – Feronimus Dec 19 '17 at 19:04
I've updated my answer with one suggestion (using Tick property) – Amittai Shapira Dec 19 '17 at 19:15

Use DateTime.ToFileTime and FromFileTime through file name string

1 Answers1