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 %>