[RESOLVED] Getting the number from the string

[MrGTI]

Hi Guys.

I am looking for a little advice on how I can do something. Please give me your suggestions.

Pretend I have some string values like this:

Document1_789123456.docx

3rd_Notice_123456789_Final.pdf

001002003_SallySample_Upload.xls

I know I can use RegEx to find out if the strings have a nine digit employee number in the string. But I also want to get the 9 digit employee number from the file.

How would you recommend I get the 9 digit employee number? It’s important that I get all 9 digits. If the number if 8 digits long, then it’s not the employee number.

Since RegEx only tells me if the value exists (and not where in the string it exists), I was thinking maybe I could loop through the string and count how many numbers in a row I find.

What do you think? Is there a better way?

[dunfiddlin]

Since RegEx only tells me if the value exists (and not where in the string it exists)

Er ... I suggest you revise RegEx. The whole point it is to extract sections of text.

[DataMiser]

And if you don;t want to use regex you could drop the extension and split the filename on the underscore then loop through the resulting array to locate the element where the 9 digit number occurs.

[MrGTI]

I went back and looked at all my RegEx examples, and none of them have anything about extracting anything from the string - they're all comparison checks, like if an email address is valid. So i looked further, and i see that Match has an Index property - the location of where it found the match. Thanks dunfiddlin!

Any ideas on how to create the Regular Expression to locate the nine digit number? I've always had trouble creating those expressions. How do you make the [0-9] span 9 numbers in a row?

[Evil_Giraffe]

So i looked further, and i see that Match has an Index property - the location of where it found the match.

You're making this harder than it needs to be. You don't extract the index of the match and then go back to the original string. Your regex should include a Capture Group that is returned as part of the regex result. You can simply get these values out of each Match. You do this with parentheses.

Any ideas on how to create the Regular Expression to locate the nine digit number? I've always had trouble creating those expressions. How do you make the [0-9] span 9 numbers in a row?

You specify that you want to repeat the element 9 times with the appropriate command in the regex. Use braces for this.

Do you have a Regex reference? Sounds like you could do with one.

[Grimfort]

Have a look at this site, its an excellent place for testing out how regex works: http://gskinner.com/RegExr/

Just paste in your example filesnames above, and a regex sample at the top that looks like this:

([0-9]{9})

Which very simply says group ready for extract (brackets) the character [0-9] exactly {9} times.

There is an example here, http://msdn.microsoft.com/en-us/library/twcw2f1c.aspx that you can look at to see how you extract the captures (groups) of the numbers, the example is overkill for what you need as you expect only 1 extract.

[MrGTI]

Thanks for that shove in the right direction Grimfort. The MSDN page proved usefull. I was able to build a function the get the Employee number in just a few simple lines of code.

    Private Function GetEmployeeNumber(ByVal sInputText As String) As String
        Dim sReturn As String = ""
        Try
            Dim r As Regex = New Regex("([0-9]{9})", RegexOptions.IgnoreCase)
            Dim m As Match = r.Match(sInputText)
            If m.Success = True Then sReturn = m.Value
        Catch Exp As Exception
            sReturn = ""
        End Try
        Return sReturn
    End Function

Thanks guys!