MS Access Visual Basic - generate random string in

Question

We have that old software (made by one of the first employees many years ago) in company that uses Microsoft Access to run. Boss asked me to add a random string generation in the specific text box on click but i have no idea how to do that. I dont have any Microsoft Access programming experience, thats why i am askin you to help.

I managed to create button and text field so far. Thats where it stops. I also managed to access the code for the button action:

Private Sub command133_Click()

End Sub

Answer 1

Try this function:

Public Function GetRandomString(ByVal iLength As Integer) As String
    Dim sResult As String = ""
    Dim rdm As New Random()

    For i As Integer = 1 To iLength
        sResult &= ChrW(rdm.Next(32, 126))
    Next

    Return sResult
End Function

Answer 2

Workin on @Bathsheba code, I did this. It will generate a random string with the number of characters you'd like.

Code :

Public Function GenerateUniqueSequence(numberOfCharacters As Integer) As String

    Dim random As String  ' * 8 'fixed length string with 8 characters
    Dim j As Integer
    Dim ch As Integer   ' each character

    random = ""

    For j = 1 To numberOfCharacters
        random = random & GenerateRandomAlphaNumericCharacter
    Next

    GenerateUniqueSequence = random

End Function

Public Function GenerateRandomAlphaNumericCharacter() As String

    'Numbers : 48 is '0', 57  is '9'
    'LETTERS : 65 is 'A', 90  is 'Z'
    'letters : 97 is 'a', 122 is 'z'

    GenerateRandomAlphaNumericCharacter = ""

    Dim i As Integer

    Randomize
    i = (Rnd() * 2) + 1 'One chance out of 3 to choose one of 3 catégories

    Randomize
    Select Case i
        Case 1 'Numbers
            GenerateRandomAlphaNumericCharacter = Chr(Rnd() * 9 + 48)
        Case 2 'LETTERS
            GenerateRandomAlphaNumericCharacter = Chr(Rnd() * 25 + 65)
        Case 3 'letters
            GenerateRandomAlphaNumericCharacter = Chr(Rnd() * 25 + 97)
    End Select

End Function

I use it with random number of characters, like this :

'Generates random Session ID between 15 and 30 alphanumeric characters
SessionID = GenerateUniqueSequence(Rnd * 15 + 15)

Result :

s8a8qWOmoDvC4jKRjPr5hOY12u 26
TB24qZ4cNfr6EdyY0J 18
6LZRQ9P5WHLNd71LIdqJ 20
KPN0RmlhhJKnVzPTkW 18
R2pNOKWJMKl9KpSoIV2egUNTEb1QC2 30
X8jHuupP6SvEI8Dt2wJi 20

Answer 3

This is one way, will work in Access VBA (which is an older basic than vb.net). It will generate a string with letters and numbers.

Sub test()

    Dim s As String * 8 'fixed length string with 8 characters
    Dim n As Integer
    Dim ch As Integer 'the character
    For n = 1 To Len(s) 'don't hardcode the length twice
        Do
            ch = Rnd() * 127 'This could be more efficient.
            '48 is '0', 57 is '9', 65 is 'A', 90 is 'Z', 97 is 'a', 122 is 'z'.
        Loop While ch < 48 Or ch > 57 And ch < 65 Or ch > 90 And ch < 97 Or ch > 122
        Mid(s, n, 1) = Chr(ch) 'bit more efficient than concatenation
    Next

    Debug.Print s

End Sub