This is a simple yet highly customizable function that allows you to generate random strings using VBScript that you can use in your ASP/VBScript applications. The random strings can be used for various purposes, including:

- Login Systems
- Random password for new registrations
- Random password for users requesting password reset

- Referral Codes
- Promotional Codes
- Primary Keys for tables where using integers as primary keys is not desirable

The following code is a VBScript translation of the php random string function I wrote earlier. It generates an 8 character long random string that contains 1 digit:

<% function RandomString() Randomize() dim CharacterSetArray CharacterSetArray = Array(_ Array(7, "abcdefghijklmnopqrstuvwxyz"), _ Array(1, "0123456789") _ ) dim i dim j dim Count dim Chars dim Index dim 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 RandomString = TempCopy end function %>

##### Sample Output

jogwafs2 uuwigi6r cj3gpdbn 7ifmzdhq yvceae4x qm8dxhik 4kyhyevr evk9hmcb

For better readability and ease of customization, I have split the `CharacterSetArray`

definition on to multiple lines. This code relies on VBScript Arrays and the following functions:

- Randomize()
- Rnd()
- Int()
- Len()
- Mid()

#### Customization

With minor changes to the `CharacterSetArray`

, you can customize the length and characters of the generated strings.

##### Complex password that contains 1 digit and 1 symbol

<% function RandomString() Randomize() dim CharacterSetArray CharacterSetArray = Array(_ Array(6, "abcdefghijklmnopqrstuvwxyz"), _ Array(1, "0123456789"), _ Array(1, "!@#$+-*&?:") _ ) dim i dim j dim Count dim Chars dim Index dim 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 RandomString = TempCopy end function %>

##### Sample Output

zb5&bxjr pd$8lrlu yljmoq:5 $xsaxc6r sf!n3mho tpg+t4pr @zykc1pb ln3ep-vk

##### Even more complex password that contains 1 upper-case character, 1 digit and 1 symbol

<% function RandomString() Randomize() dim CharacterSetArray CharacterSetArray = Array(_ Array(5, "abcdefghijklmnopqrstuvwxyz"), _ Array(1, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"), _ Array(1, "0123456789"), _ Array(1, "!@#$+-*&?:") _ ) dim i dim j dim Count dim Chars dim Index dim 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 RandomString = TempCopy end function %>

##### Sample Output

cg9hm$Yy Mmp&j1kp kipww7H+ ?oVjny9b Qjq5lgi- sd:7Elnp *kaxgl4Z xqjc5jN!

##### Referral code containing mix of digits and upper-case characters

<% function RandomString() Randomize() dim CharacterSetArray CharacterSetArray = Array(_ Array(4, "ABCDEFGHIJKLMNOPQRSTUVWXYZ"), _ Array(4, "0123456789") _ ) dim i dim j dim Count dim Chars dim Index dim 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 RandomString = TempCopy end function %>

##### Sample Output

9HL284CB OTH357O8 DY6W32J0 4KI134MJ QP190HE9 KDU35A67 PY03F3S2 3EBV871R