Home » What is the regex pattern for datetime (2008-09-01 12:35:45 )?

What is the regex pattern for datetime (2008-09-01 12:35:45 )?

Solutons:


@Espo: I just have to say that regex is incredible. I’d hate to have to write the code that did something useful with the matches, such as if you wanted to actually find out what date and time the user typed.

It seems like Tom’s solution would be more tenable, as it is about a zillion times simpler and with the addition of some parentheses you can easily get at the values the user typed:

(d{4})-(d{2})-(d{2}) (d{2}):(d{2}):(d{2})

If you’re using perl, then you can get the values out with something like this:

$year = $1;
$month = $2;
$day = $3;
$hour = $4;
$minute = $5;
$second = $6;

Other languages will have a similar capability. Note that you will need to make some minor mods to the regex if you want to accept values such as single-digit months.

A simple version that will work for the format mentioned, but not all the others as per @Espos:

(d{4}-d{2}-d{2} d{2}:d{2}:d{2}) 

http://regexlib.com/REDetails.aspx?regexp_id=610

^(?=d)(?:(?:31(?!.(?:0?[2469]|11))|(?:30|29)(?!.0?2)|29(?=.0?2.(?:(?:(?:1[6-9]|[2-9]d)?(?:0[48]|[2468][048]|[13579][26])|(?:(?:16|[2468][048]|[3579][26])00)))(?:x20|$))|(?:2[0-8]|1d|0?[1-9]))([-./])(?:1[012]|0?[1-9])1(?:1[6-9]|[2-9]d)?dd(?:(?=x20d)x20|$))?(((0?[1-9]|1[012])(:[0-5]d){0,2}(x20[AP]M))|([01]d|2[0-3])(:[0-5]d){1,2})?$


This RE validates both dates and/or
times patterns. Days in Feb. are also
validated for Leap years. Dates: in
dd/mm/yyyy or d/m/yy format between
1/1/1600 – 31/12/9999. Leading zeroes
are optional. Date separators can be
either matching dashes(-), slashes(/)
or periods(.) Times: in the hh:MM:ss
AM/PM 12 hour format (12:00 AM –
11:59:59 PM) or hh:MM:ss military time
format (00:00:00 – 23:59:59). The 12
hour time format: 1) may have a
leading zero for the hour. 2) Minutes
and seconds are optional for the 12
hour format 3) AM or PM is required
and case sensitive. Military time 1)
must have a leading zero for all hours
less than 10. 2) Minutes are
manditory. 3) seconds are optional.
Datetimes: combination of the above
formats. A date first then a time
separated by a space. ex) dd/mm/yyyy
hh:MM:ss


Edit: Make sure you copy the RegEx from the regexlib.com website as StackOverflow sometimes removes/destroys special chars.

Related Solutions

How can I stop applications and services from running?

First Things First You may have some misconceptions about how Android works and what's really happening when a service is running or an app is in the background. See also: Do I really need to install a task manager? Most apps (e.g., ones you launch manually)...

How do I reset a lost administrative password?

By default the first user's account is an administrative account, so if the UI is prompting you for a password it's probably that person's user password. If the user doesn't remember their password you need to reset it. To do this you need to boot into recovery...

How can I use environment variables in Nginx.conf

From the official Nginx docker file: Using environment variables in nginx configuration: Out-of-the-box, Nginx doesn't support using environment variables inside most configuration blocks. But envsubst may be used as a workaround if you need to generate your...

Difference between .bashrc and .bash_profile

Traditionally, when you log into a Unix system, the system would start one program for you. That program is a shell, i.e., a program designed to start other programs. It's a command line shell: you start another program by typing its name. The default shell, a...

Custom query with Castle ActiveRecord

In this case what you want is HqlBasedQuery. Your query will be a projection, so what you'll get back will be an ArrayList of tuples containing the results (the content of each element of the ArrayList will depend on the query, but for more than one value will...

What is the “You have new mail” message in Linux/UNIX?

Where is this mail? It's likely to be in the spool file: /var/mail/$USER or /var/spool/mail/$USER are the most common locations on Linux and BSD. (Other locations are possible – check if $MAIL is set – but by default, the system only informs you about...

How can I find the implementations of Linux kernel system calls?

System calls aren't handled like regular function calls. It takes special code to make the transition from user space to kernel space, basically a bit of inline assembly code injected into your program at the call site. The kernel side code that "catches" the...

Is a composite index also good for queries on the first field?

It certainly is. We discussed that in great detail under this related question: Working of indexes in PostgreSQL Space is allocated in multiples of MAXALIGN, which is typically 8 bytes on a 64-bit OS or (much less common) 4 bytes on a 32-bit OS. If you are not...

Explaining computational complexity theory

Hoooo, doctoral comp flashback. Okay, here goes. We start with the idea of a decision problem, a problem for which an algorithm can always answer "yes" or "no." We also need the idea of two models of computer (Turing machine, really): deterministic and...

Building a multi-level menu for umbraco

First off, no need pass the a parent parameter around. The context will transport this information. Here is the XSL stylesheet that should solve your problem: <!-- update this variable on how deep your menu should be --> <xsl:variable...

How to generate a random string?

My favorite way to do it is by using /dev/urandom together with tr to delete unwanted characters. For instance, to get only digits and letters: tr -dc A-Za-z0-9 </dev/urandom | head -c 13 ; echo '' Alternatively, to include more characters from the OWASP...

How to copy a file from a remote server to a local machine?

The syntax for scp is: If you are on the computer from which you want to send file to a remote computer: scp /file/to/send username@remote:/where/to/put Here the remote can be a FQDN or an IP address. On the other hand if you are on the computer wanting to...

What is the difference between curl and wget?

The main differences are: wget's major strong side compared to curl is its ability to download recursively. wget is command line only. There's no lib or anything, but curl's features are powered by libcurl. curl supports FTP, FTPS, HTTP, HTTPS, SCP, SFTP, TFTP,...

Using ‘sed’ to find and replace [duplicate]

sed is the stream editor, in that you can use | (pipe) to send standard streams (STDIN and STDOUT specifically) through sed and alter them programmatically on the fly, making it a handy tool in the Unix philosophy tradition; but can edit files directly, too,...

How do I loop through only directories in bash?

You can specify a slash at the end to match only directories: for d in */ ; do echo "$d" done If you want to exclude symlinks, use a test to continue the loop if the current entry is a link. You need to remove the trailing slash from the name in order for -L to...

How to clear journalctl

The self maintenance method is to vacuum the logs by size or time. Retain only the past two days: journalctl --vacuum-time=2d Retain only the past 500 MB: journalctl --vacuum-size=500M man journalctl for more information. You don't typically clear the journal...