ASP验证码生成类与实现

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'一个简单的asp生成图片验证码类，将这段代码保存为code.asp文件，使用示例在下方
'我佛山人@2005.8.23
'此类由上面的网友所做，为尊重作者，建议在使用时保留此信息
Option Explicit
Response.Buffer = true
Class ValidCode
    Private PNoise
    Private PBgColor
    Private PLength
    Private charSet
    Private charSetCount

    '噪点
    Public Property Let Noise(ByVal Value)
        If IsNumeric(Value) Then
            PNoise = CInt(Value) Mod 100
        End If
    End Property
    Public Property Get Noise()
        Noise = PNoise
    End Property

    '背景颜色
    Public Property Let BgColor(ByVal Value)
        PBgColor = Value
    End Property
    Public Property Get BgColor()
        BgColor = PBgColor
    End Property

    '验证码长度
    Public Property Let Length(ByVal Value)
        PLength = Value
        If PLength < 2 Then PLength = 2
    End Property
    Public Property Get Length()
        Length = PLength
    End Property

    Private Sub Class_Initialize()
        charSet = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
        charSetCount = Len(charSet)
        Noise = 6
        Length = 4
        BgColor = ChrB(250) & ChrB(250) & ChrB(240)
    End Sub    
    Private Sub Class_Terminate()
    End Sub

    Public Sub Generate(sessionName)
        ' 字符数据
        Dim numberSet(35)
        numberSet(0) = "1110000111110111101111011110111101001011110100101111010010111101001011110111101111011110111110000111"
        numberSet(1) = "1111011111110001111111110111111111011111111101111111110111111111011111111101111111110111111100000111"
        numberSet(2) = "1110000111110111101111011110111111111011111111011111111011111111011111111011111111011110111100000011"
        numberSet(3) = "1110000111110111101111011110111111110111111100111111111101111111111011110111101111011110111110000111"
        numberSet(4) = "1111101111111110111111110011111110101111110110111111011011111100000011111110111111111011111111000011"
        numberSet(5) = "1100000011110111111111011111111101000111110011101111111110111111111011110111101111011110111110000111"
        numberSet(6) = "1111000111111011101111011111111101111111110100011111001110111101111011110111101111011110111110000111"