Generate random alphanumeric string - vb.net

Question

I am trying to generate a random code in vb.net like this
Dim r As New Random
Response.Write(r.Next())
But I want to generate code with 6 digits and should be alphanumeric like thie A12RV1 and all codes should be like this.
I have tried vb.net random class but I am unable to do that like as I want. I want to get the alphanumeric code each time when I execute the code. How can i achieve this in vb.net?

Answer 1

Try something like this:
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
Or you can do the common random string defining the valid caracters:
Public Function GenerateRandomString(ByRef iLength As Integer) As String
Dim rdm As New Random()
Dim allowChrs() As Char = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLOMNOPQRSTUVWXYZ0123456789".ToCharArray()
Dim sResult As String = ""
For i As Integer = 0 To iLength - 1
sResult += allowChrs(rdm.Next(0, allowChrs.Length))
Next
Return sResult
End Function

Answer 2

I think this will suits your requirement,
Private sub GenerateString()
Dim xCharArray() As Char = "ABCDEFGHIJKLMNOPQRSTUVWXYZ".ToCharArray
Dim xNoArray() As Char = "0123456789".ToCharArray
Dim xGenerator As System.Random = New System.Random()
Dim xStr As String = String.Empty
While xStr.Length < 6
If xGenerator.Next(0, 2) = 0 Then
xStr &= xCharArray(xGenerator.Next(0, xCharArray.Length))
Else
xStr &= xNoArray(xGenerator.Next(0, xNoArray.Length))
End If
End While
MsgBox(xStr)
End Sub
Note: Tested With IDE
EDIT: Modified according to SYSDRAGON's Comment