ASP实现无组件生成验证码-GIF格式

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ASP实现无组件生成验证码-GIF格式

<%
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

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