RC4 Encryption in VB

Here's the code:

	Public Function RC4(ByVal Expression As String, ByVal Password As String) As String
	On Error Resume Next
	Dim RB(0 To 255) As Integer, X As Long, Y As Long, Z As Long, Key() As Byte, ByteArray() As Byte, Temp As Byte
	If Len(Password) = 0 Then
	Exit Function
	End If
	If Len(Expression) = 0 Then
	Exit Function
	End If
	If Len(Password) > 256 Then
	Key() = StrConv(Left$(Password, 256), vbFromUnicode)
	Else
	Key() = StrConv(Password, vbFromUnicode)
	End If
	For X = 0 To 255
	RB(X) = X
	Next X
	X = 0
	Y = 0
	Z = 0
	For X = 0 To 255
	Y = (Y + RB(X) + Key(X Mod Len(Password))) Mod 256
	Temp = RB(X)
	RB(X) = RB(Y)
	RB(Y) = Temp
	Next X
	X = 0
	Y = 0
	Z = 0
	ByteArray() = StrConv(Expression, vbFromUnicode)
	For X = 0 To Len(Expression)
	Y = (Y + 1) Mod 256
	Z = (Z + RB(Y)) Mod 256
	Temp = RB(Y)
	RB(Y) = RB(Z)
	RB(Z) = Temp
	ByteArray(X) = ByteArray(X) Xor (RB((RB(Y) + RB(Z)) Mod 256))
	Next X
	RC4 = StrConv(ByteArray, vbUnicode)
	End Function

view raw rc4.vb hosted with ❤ by GitHub