当前位置: 首页 > 图文教程 > 网络编程 > ASP > ASP实现无组件生成验证码-GIF格式

ASP
ASP正则表达式技巧
ASP Access实现网站计数器(访问量)
ASP新闻分页,将一篇过长的文章分页,生成静态页面
一些关于asp 购物车的想法
一个sql查询器,自动画表格填字段
ASP实现文件直接下载的代码
把网页中的(电话,qq等数字)生成图片的ASP程序
asp长文章用分页符来分页显示
Asp函数介紹(37个常用函数)
ASP中的面向对象类
分页实现方法的性能比较
asp ajax跨域提交数据
asp修改文件和文件夹的名字的代码
ASP 多关键词查询实例代码
asp被杀毒软件误删的解决方法
asp 多关键词搜索的简单实现方法
asp 根据IP地址自动判断转向分站的代码
asp dictionary对象的用法
ASP 千万级数据分页的存储过程
ASP隐藏真实文件的下载功能实现代码

ASP实现无组件生成验证码-GIF格式


出处:互联网   整理: 软晨网(RuanChen.com)   发布: 2009-08-14   浏览: 252 ::
收藏到网摘: n/a

<%
Option Explicit ' 显示声明

Class Com_GifCode_Class
'''''''''''''''''''''''''''''''''''''''''''''
' Author: Layen [email protected] 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