asp无组件生成验证码 GIF图片格式

复制代码 代码如下:

<%

Option Explicit ' 显示声明

Class Com_GifCode_Class

'''''''''''''''''''''''''''''''''''''''''''''

' Author: Layen support@ssaw.net 84815733(QQ)

' Thanks: Laomi, Laomiao, NetRube

' 2006-01-02

'''''''''''''''''''''''''''''''''''''''''''''

Public Noisy, Count, Width, Height, Angle, Offset, Border

Private Graph(), Margin(3)

Private Sub Class_Initialize()

Randomize

Noisy = 16 ' 干扰点出现的概率

Count = 4 ' 字符数量

Width = 80 ' 图片宽度

Height = 20 ' 图片高度

Angle = 2 ' 角度随机变化量

Offset = 20 ' 偏移随机变化量

Border = 1 ' 边框大小

End Sub

Public Function Create()

Const cCharSet = "123456789"

Dim i, x, y

Dim vValidCode : vValidCode = ""

Dim vIndex

ReDim Graph(Width-1, Height-1)

For i = 0 To Count - 1

vIndex = Int(Rnd * Len(cCharSet))

vValidCode = vValidCode + Mid(cCharSet, vIndex+1 , 1)

SetDraw vIndex, i

Next

Create = vValidCode

End Function

Sub SetDot(pX, pY)

If pX * (Width-pX-1) >= 0 And pY * (Height-pY-1) >= 0 Then

Graph(pX, pY) = 1

End If

End Sub

Public Sub SetDraw(pIndex, pNumber)

' 字符数据

Dim DotData(8)

DotData(0) = Array(30, 15, 50, 1, 50, 100)

DotData(1) = Array(1 ,34 ,30 ,1 ,71, 1, 100, 34, 1, 100, 93, 100, 100, 86)

DotData(2) = Array(1, 1, 100, 1, 42, 42, 100, 70, 50, 100, 1, 70)

DotData(3) = Array(100, 73, 6, 73, 75, 6, 75, 100)

DotData(4) = Array(100, 1, 1, 1, 1, 50, 50, 35, 100, 55, 100, 80, 50, 100, 1, 95)

DotData(5) = Array(100, 20, 70, 1, 20, 1, 1, 30, 1, 80, 30, 100, 70, 100, 100, 80, 100, 60, 70, 50, 30, 50, 1, 60)

DotData(6) = Array(6, 26, 6, 6, 100, 6, 53, 100)

DotData(7) = Array(100, 30, 100, 20, 70, 1, 30, 1, 1, 20, 1, 30, 100, 70, 100, 80, 70, 100, 30, 100, 1, 80, 1, 70, 100, 30)

DotData(8) = Array(1, 80, 30, 100, 80, 100, 100, 70, 100, 20, 70, 1, 30, 1, 1, 20, 1, 40, 30, 50, 70, 50, 100, 40)

Dim vExtent : vExtent = Width / Count

Margin(0) = Border + vExtent * (Rnd * Offset) / 100 + Margin(1)

Margin(1) = vExtent * (pNumber + 1) - Border - vExtent * (Rnd * Offset) / 100

Margin(2) = Border + Height * (Rnd * Offset) / 100

Margin(3) = Height - Border - Height * (Rnd * Offset) / 100

Dim vStartX, vEndX, vStartY, vEndY

Dim vWidth, vHeight, vDX, vDY, vDeltaT

Dim vAngle, vLength

vWidth = Int(Margin(1) - Margin(0))

vHeight = Int(Margin(3) - Margin(2))

' 起始坐标

vStartX = Int((DotData(pIndex)(0)-1) * vWidth / 100)

vStartY = Int((DotData(pIndex)(1)-1) * vHeight / 100)

Dim i, j

For i = 1 To UBound(DotData(pIndex), 1)/2

If DotData(pIndex)(2*i-2) <> 0 And DotData(pIndex)(2*i) <> 0 Then

' 终点坐标

vEndX = (DotData(pIndex)(2*i)-1) * vWidth / 100

vEndY = (DotData(pIndex)(2*i+1)-1) * vHeight / 100

' 横向差距

vDX = vEndX - vStartX

' 纵向差距

vDY = vEndY - vStartY

' 倾斜角度

If vDX = 0 Then

vAngle = Sgn(vDY) * 3.14/2

Else

vAngle = Atn(vDY / vDX)

End If

' 两坐标距离

If Sin(vAngle) = 0 Then

vLength = vDX

Else

vLength = vDY / Sin(vAngle)

End If

' 随机转动角度

vAngle = vAngle + (Rnd - 0.5) * 2 * Angle * 3.14 * 2 / 100

vDX = Int(Cos(vAngle) * vLength)

vDY = Int(Sin(vAngle) * vLength)

If Abs(vDX) > Abs(vDY) Then vDeltaT = Abs(vDX) Else vDeltaT = Abs(vDY)

For j = 1 To vDeltaT

SetDot Margin(0) + vStartX + j * vDX / vDeltaT, Margin(2) + vStartY + j * vDY / vDeltaT

Next

vStartX = vStartX + vDX

vStartY = vStartY + vDY

End If

Next

End Sub

Public Sub Output()

Response.Expires = -9999

Response.AddHeader "pragma", "no-cache"

Response.AddHeader "cache-ctrol", "no-cache"

Response.ContentType = "image/gif"

' 文件类型

Response.BinaryWrite ChrB(Asc("G")) & ChrB(Asc("I")) & ChrB(Asc("F"))

' 版本信息

Response.BinaryWrite ChrB(Asc("8")) & ChrB(Asc("9")) & ChrB(Asc("a"))

' 逻辑屏幕宽度

Response.BinaryWrite ChrB(Width Mod 256) & ChrB((Width \ 256) Mod 256)

' 逻辑屏幕高度

Response.BinaryWrite ChrB(Height Mod 256) & ChrB((Height \ 256) Mod 256)

Response.BinaryWrite ChrB(128) & ChrB(0) & ChrB(0)

' 全局颜色列表

Response.BinaryWrite ChrB(255) & ChrB(255) & ChrB(255)

Response.BinaryWrite ChrB(0) & ChrB(85) & ChrB(255)

' 图象标识符

Response.BinaryWrite ChrB(Asc(","))

Response.BinaryWrite ChrB(0) & ChrB(0) & ChrB(0) & ChrB(0)

' 图象宽度

Response.BinaryWrite ChrB(Width Mod 256) & ChrB((Width \ 256) Mod 256)

' 图象高度

Response.BinaryWrite ChrB(Height Mod 256) & ChrB((Height \ 256) Mod 256)

Response.BinaryWrite ChrB(0) & ChrB(7) & ChrB(255)

Dim x, y, i : i = 0

For y = 0 To Height - 1

For x = 0 To Width - 1

If Rnd < Noisy / 100 Then

Response.BinaryWrite ChrB(1-Graph(x, y))

Else

If x * (x-Width) = 0 Or y * (y-Height) = 0 Then

Response.BinaryWrite ChrB(Graph(x, y))

Else

If Graph(x-1, y) = 1 Or Graph(x, y) Or Graph(x, y-1) = 1 Then

Response.BinaryWrite ChrB(1)

Else

Response.BinaryWrite ChrB(0)

End If

End If

End If

If (y * Width + x + 1) Mod 126 = 0 Then

Response.BinaryWrite ChrB(128)

i = i + 1

End If

If (y * Width + x + i + 1) Mod 255 = 0 Then

If (Width*Height - y * Width - x - 1) > 255 Then

Response.BinaryWrite ChrB(255)

Else

Response.BinaryWrite ChrB(Width * Height Mod 255)

End If

End If

Next

Next

Response.BinaryWrite ChrB(128) & ChrB(0) & ChrB(129) & ChrB(0) & ChrB(59)

End Sub

End Class

Dim mCode

Set mCode = New Com_GifCode_Class

Session("GetCode") = mCode.Create()

mCode.Output()

Set mCode = Nothing

%>