?
Solved

regular expression for date

Posted on 2003-11-12
12
Medium Priority
?
913 Views
Last Modified: 2008-02-01
Hi,

              Could anyone  provide me a regular expression for  date in MMDDYYYY format?....

thank you
0
Comment
Question by:sunny1510
  • 4
  • 4
  • 2
  • +2
12 Comments
 
LVL 48

Expert Comment

by:Mikal613
ID: 9731596
Can you explain please?
0
 

Author Comment

by:sunny1510
ID: 9731655
I am validating a date entered in a text box.....The user is only allowed to enter the date in mmddyyyy format......i know checking the format is easy with regex .......but i want the regular expression to check if it is a valid date.....
0
 
LVL 48

Expert Comment

by:Mikal613
ID: 9731720
Well if in your Glabal Region Settings if your Setting is set to mmddyyyy then just use IsDate()
0
Get free NFR key for Veeam Availability Suite 9.5

Veeam is happy to provide a free NFR license (1 year, 2 sockets) to all certified IT Pros. The license allows for the non-production use of Veeam Availability Suite v9.5 in your home lab, without any feature limitations. It works for both VMware and Hyper-V environments

 

Author Comment

by:sunny1510
ID: 9731770
Thanks for the response  Milka..The date is being validated when the textbox loses focus.....for certain date fields i also allow default value of 00000000 or a blank field. In that case this isdate() will give me an error. That is y i thought i will use regex.
0
 
LVL 48

Expert Comment

by:Mikal613
ID: 9731792
so

If txtDAte.text = "" or txtDAte.text  = "00000000"  then
else
    if not isdate(txtdate.text) then Msgbox "Wrong Date"
end if

 
0
 
LVL 44

Expert Comment

by:Arthur_Wood
ID: 9731820
rahter than requiring the user to enter the date as a sequence of digits (by the way, since the entry IS a sequence of digits, a regex will not help, since any digit is valid, but you want to be sure that they are no just digits, but also make up a valid date, and that is NOT what regex is used for), why do you not prenet the user with a Calendar control, and they you are CERTAIN they have picked a valid date?

AW
0
 
LVL 28

Expert Comment

by:iboutchkine
ID: 9731837
Here is an example. I think you will find it helpful

 ' The following pattern checks whether the input string is a date in the
        ' format mm-dd-yy or mm-dd-yyyy. Key pattern elements used are:
        '
        '   \d{1,2}     Month and day numbers can have 1 or 2 digits. The use of
        '               (\d{4}|\d{2}) means the year can have 2 or 4 digits.
        '   (/|-)       Either the slash or the dash are valid date separators.
        '   \1          The separator used for the day and year must be the same
        '               as the separator used for month and day. The 1 refers to the
        '               first numbered group, defined by parentheses, e.g, (/|-).
        '  
        ' You could improve on this pattern by ensuring that digits do not start with
        ' a zero and that they are in a valid numerical range.
        '
        If Not Regex.IsMatch(txtDate.Text, _
            "^\s*\d{1,2}(/|-)\d{1,2}\1(\d{4}|\d{2})\s*$") Then

            txtDate.ForeColor = Color.Red
            IsValid = False
        Else
            txtDate.ForeColor = Color.Black
        End If
0
 

Author Comment

by:sunny1510
ID: 9731877
I have a number of text boxes in my app.....what if there is  a situation where one of these will accepts a value of "" and the other other textbox  needs a valid date .... In that case if the user enters a "" and exits... the isdate() fuction will accept it.
0
 

Author Comment

by:sunny1510
ID: 9731961
Hi all,

       Here i found a link where they have used regular expression for validating dates of mm/ddy/yyyy format.I am trying to use this regex since this appliction is a data entry program and i would prefer the user keying it in a text box.....Also I cannot write one function which will handle all the date validations since every date-text box has a  different default value......

http://www.regxlib.com/REDetails.aspx?regexp_id=279

please let me know if there is any other way of doing this...... thanks
0
 
LVL 48

Expert Comment

by:Mikal613
ID: 9732154
why dont you use a masked Edit control

you can set your MASK?
0
 
LVL 9

Expert Comment

by:malharone
ID: 9733127
i'll recommend what i've always recommended for regex.
great for building & testing
http://www.codeproject.com/dotnet/expresso.asp?target=expresso
(?<Month>\d{1,2})/(?<Day>\d{1,2})/(?<Year>(?:\d{4}|\d{2}))(?x)

it includes a predefined regex for data.
however it'll NOT check for proper 'date value' given the month number.
so you could enter 4/31/2001 and it'll accept it.
So what you'd need to do is call
dim yourdatestring as string="4/31/2001"
if isDate(yourDateString)=false then
  messagebox.show(yourdateString & " is not a valid date")
else
  'all is OK
end if
0
 
LVL 9

Accepted Solution

by:
malharone earned 280 total points
ID: 9733148
0

Featured Post

[Webinar] Cloud and Mobile-First Strategy

Maybe you’ve fully adopted the cloud since the beginning. Or maybe you started with on-prem resources but are pursuing a “cloud and mobile first” strategy. Getting to that end state has its challenges. Discover how to build out a 100% cloud and mobile IT strategy in this webinar.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

In my previous two articles we discussed Binary Serialization (http://www.experts-exchange.com/A_4362.html) and XML Serialization (http://www.experts-exchange.com/A_4425.html). In this article we will try to know more about SOAP (Simple Object Acces…
Today I had a very interesting conundrum that had to get solved quickly. Needless to say, it wasn't resolved quickly because when we needed it we were very rushed, but as soon as the conference call was over and I took a step back I saw the correct …
Despite its rising prevalence in the business world, "the cloud" is still misunderstood. Some companies still believe common misconceptions about lack of security in cloud solutions and many misuses of cloud storage options still occur every day. …
Whether it be Exchange Server Crash Issues, Dirty Shutdown Errors or Failed to mount error, Stellar Phoenix Mailbox Exchange Recovery has always got your back. With the help of its easy to understand user interface and 3 simple steps recovery proced…
Suggested Courses
Course of the Month15 days, 17 hours left to enroll

850 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question