運作效果如圖
用法如下:
///<summary>
/// 顯示驗證碼
///</summary>
///<returns>驗證碼</returns>
privatevoid GetVerifyCode()
{
VerifyCodeImage verifyCodeImage =new VerifyCodeImage();
// 取随機碼
string code = verifyCodeImage.CreateVerifyCode().ToUpper();
// 輸出圖檔
this.picVerifyCode.Image = verifyCodeImage.CreateImage(code, 3);
this.picVerifyCode.Tag = code;
}
privatevoid picVerifyCode_DoubleClick(object sender, EventArgs e)
this.GetVerifyCode();
// this.txtVerifyCode.Clear();
this.txtVerifyCode.SelectAll();
this.txtVerifyCode.Focus();
源碼如下:
//-----------------------------------------------------------------
// All Rights Reserved , Copyright (C) 2011 , Hairihan TECH, Ltd.
using System;
using System.Drawing;
using System.Web;
namespace DotNet.Utilities
{
publicclass VerifyCodeImage
{
public VerifyCodeImage()
#region 驗證碼長度(預設4個驗證碼的長度)
int length =4;
publicint Length
get { return length; }
set { length = value; }
#endregion
#region 驗證碼字型大小(為了顯示扭曲效果,預設40像素,可以自行修改)
int fontSize =50;
publicint FontSize
get { return fontSize; }
set { fontSize = value; }
#region 邊框補(預設1像素)
int padding =2;
publicint Padding
get { return padding; }
set { padding = value; }
#region 是否輸出燥點(預設不輸出)
bool chaos =true;
publicbool Chaos
get { return chaos; }
set { chaos = value; }
#region 輸出燥點的顔色(預設灰色)
Color chaosColor = Color.LightGray;
public Color ChaosColor
get { return chaosColor; }
set { chaosColor = value; }
#region 自定義背景色(預設白色)
Color backgroundColor = Color.White;
public Color BackgroundColor
get { return backgroundColor; }
set { backgroundColor = value; }
#region 自定義随機顔色數組
Color[] colors = { Color.Black, Color.Red, Color.DarkBlue, Color.Green, Color.Orange, Color.Brown, Color.DarkCyan, Color.Purple };
public Color[] Colors
get { return colors; }
set { colors = value; }
#region 自定義字型數組
string[] fonts = { "Arial", "Georgia" };
publicstring[] Fonts
get { return fonts; }
set { fonts = value; }
#region 自定義随機碼字元串序列(使用逗号分隔)
// 去除 0,1,i,l,o,I,L,O
string codeSerial ="2,3,4,5,6,7,8,9,a,b,c,d,e,f,g,h,j,k,m,n,p,q,r,s,t,u,v,w,x,y,z,A,B,C,D,E,F,G,H,J,K,M,N,P,Q,R,S,T,U,V,W,X,Y,Z";
publicstring CodeSerial
get { return codeSerial; }
set { codeSerial = value; }
#region 産生波形濾鏡效果
//private const double PI = 3.1415926535897932384626433832795;
privateconstdouble PI2 =6.283185307179586476925286766559;
/// 正弦曲線Wave扭曲圖檔(Edit By 51aspx.com)
///<param name="srcBmp">圖檔路徑</param>
///<param name="bXDir">如果扭曲則選擇為True</param>
///<param name="nMultValue">波形的幅度倍數,越大扭曲的程度越高,一般為3</param>
///<param name="dPhase">波形的起始相位,取值區間[0-2*PI)</param>
///<returns></returns>
public System.Drawing.Bitmap TwistImage(Bitmap srcBmp, bool bXDir, double dMultValue, double dPhase)
System.Drawing.Bitmap bitmap =new Bitmap(srcBmp.Width, srcBmp.Height);
// 将位圖背景填充為白色
System.Drawing.Graphics graphics = System.Drawing.Graphics.FromImage(bitmap);
graphics.FillRectangle(new SolidBrush(System.Drawing.Color.White), 0, 0, bitmap.Width, bitmap.Height);
graphics.Dispose();
double dBaseAxisLen = bXDir ? (double)bitmap.Height : (double)bitmap.Width;
for (int i =0; i < bitmap.Width; i++)
{
for (int j =0; j < bitmap.Height; j++)
{
double dx =0;
dx = bXDir ? (PI2 * (double)j) / dBaseAxisLen : (PI2 * (double)i) / dBaseAxisLen;
dx += dPhase;
double dy = Math.Sin(dx);
// 取得目前點的顔色
int nOldX =0, nOldY =0;
nOldX = bXDir ? i + (int)(dy * dMultValue) : i;
nOldY = bXDir ? j : j + (int)(dy * dMultValue);
System.Drawing.Color color = srcBmp.GetPixel(i, j);
if (nOldX >=0&& nOldX < bitmap.Width
&& nOldY >=0&& nOldY < bitmap.Height)
{
bitmap.SetPixel(nOldX, nOldY, color);
}
}
}
return bitmap;
#region 生成校驗碼圖檔
public Bitmap CreateImage(string code, double multValue)
int fSize = FontSize;
int fWidth = fSize + Padding;
int imageWidth = (int)(code.Length * fWidth) +4+ Padding *2;
int imageHeight = fSize *2+ Padding;
System.Drawing.Bitmap bitmap =new System.Drawing.Bitmap(imageWidth, imageHeight);
Graphics graphics = Graphics.FromImage(bitmap);
graphics.Clear(BackgroundColor);
Random rand =new Random();
// 給背景添加随機生成的燥點
if (this.Chaos)
Pen pen =new Pen(ChaosColor, 0);
int c = Length *10;
for (int i =0; i < c; i++)
int x = rand.Next(bitmap.Width);
int y = rand.Next(bitmap.Height);
graphics.DrawRectangle(pen, x, y, 1, 1);
int left =0, top =0, top1 =1, top2 =1;
int n1 = (imageHeight - FontSize - Padding *2);
int n2 = n1 /4;
top1 = n2;
top2 = n2 *2;
Font font;
Brush brush;
int cindex, findex;
// 随機字型和顔色的驗證碼字元
for (int i =0; i < code.Length; i++)
cindex = rand.Next(Colors.Length -1);
findex = rand.Next(Fonts.Length -1);
font =new System.Drawing.Font(Fonts[findex], fSize, System.Drawing.FontStyle.Bold);
brush =new System.Drawing.SolidBrush(Colors[cindex]);
if (i %2==1)
top = top2;
else
top = top1;
left = i * fWidth;
graphics.DrawString(code.Substring(i, 1), font, brush, left, top);
// 畫一個邊框 邊框顔色為Color.Gainsboro
graphics.DrawRectangle(new Pen(Color.Gainsboro, 0), 0, 0, bitmap.Width -1, bitmap.Height -1);
// 産生波形
bitmap = TwistImage(bitmap, true, multValue, 4);
#region 生成随機字元碼
publicstring CreateVerifyCode(int codeLength)
if (codeLength ==0)
codeLength = Length;
string[] arr = CodeSerial.Split(',');
string code ="";
int randValue =-1;
Random random =new Random(unchecked((int)DateTime.Now.Ticks));
for (int i =0; i < codeLength; i++)
randValue = random.Next(0, arr.Length -1);
code += arr[randValue];
return code;
publicstring CreateVerifyCode()
return CreateVerifyCode(0);
#region 将建立好的圖檔輸出到頁面
/// 将建立好的圖檔輸出到頁面
///<param name="code">驗證碼</param>
///<param name="multValue">扭曲度(越大越扭曲)</param>
///<param name="httpContext">上下文</param>
publicvoid CreateImageOnPage(string code, double multValue, HttpContext httpContext)
System.IO.MemoryStream memoryStream =new System.IO.MemoryStream();
Bitmap bitmap =this.CreateImage(code, multValue);
bitmap.Save(memoryStream, System.Drawing.Imaging.ImageFormat.Jpeg);
httpContext.Response.ClearContent();
httpContext.Response.ContentType ="image/Jpeg";
httpContext.Response.BinaryWrite(memoryStream.GetBuffer());
memoryStream.Close();
memoryStream =null;
bitmap.Dispose();
bitmap =null;
}
}
本文轉自 jirigala 51CTO部落格,原文連結:http://blog.51cto.com/2347979/1197362,如需轉載請自行聯系原作者