How to generate Random value of any type based on the input

MsgBox RandomValue("char",10)
MsgBox RandomValue("num",10)
MsgBox RandomValue("alphanumeric",10)
MsgBox RandomValue("",10)

Function RandomValue(rType, Cnt)
Randomize()
dim CharacterSetArray
Select Case LCase(rType)
Case "char"
CharacterSetArray = Array(Array(Cnt, "abcdefghijklmnopqrstuvwxyz"), Array(0, ""))
Case "num"
CharacterSetArray = Array(Array(Cnt, "0123456789"), Array(0, ""))
Case "alphanumeric"
CharacterSetArray = Array(Array(Cnt/2, "abcdefghijklmnopqrstuvwxyz"), Array(Cnt/2, "0123456789"))
Case Else
CharacterSetArray = Array(Array(Cnt/2, "abcdefghijklmnopqrstuvwxyz"), Array(Cnt/2, "0123456789"))
End select
dim i,j,Count,Chars,Index,Temp
for i = 0 to UBound(CharacterSetArray)
Count = CharacterSetArray(i)(0)
Chars = CharacterSetArray(i)(1)
for j = 1 to Count
Index = Int(Rnd() * Len(Chars)) + 1
Temp = Temp & Mid(Chars, Index, 1)
next
next
dim TempCopy
do until Len(Temp) = 0
Index = Int(Rnd() * Len(Temp)) + 1
TempCopy = TempCopy & Mid(Temp, Index, 1)
Temp = Mid(Temp, 1, Index - 1) & Mid(Temp, Index + 1)
loop
RandomValue = TempCopy
End Function