//verifycode.aspx为默认生成的代码
using system; using system.data; using system.configuration; using system.collections; using system.web; using system.web.security; using system.web.ui; using system.web.ui.webcontrols.webparts; using system.web.ui.htmlcontrols; using system.drawing; using system.drawing.imaging; using system.drawing.drawing2d; using system.io; public partial class verifycode : system.web.ui.page { protected void page_load(object sender, eventargs e) { //generatevalidatecode(); generateverifyimage(4);//generateverifyimage(int length) } #region 【无刷新仿google波形扭曲彩色】验证码样式0___generatevalidatecode() private void generatevalidatecode() { this.length = this.length; this.fontsize = this.fontsize; this.chaos = this.chaos; this.backgroundcolor = this.backgroundcolor; this.chaoscolor = this.chaoscolor; this.codeserial = this.codeserial; this.colors = this.colors; this.fonts = this.fonts; this.padding = this.padding; string vnum = this.createverifycode(); //取随机码 session["validatecode"] = vnum.toupper();//取得验证码，以便后来验证 this.createimageonpage(vnum, this.context); // 输出图片 //cookie验证模式， 使用cookies取验证码的值 //response.cookies.add(new httpcookie("checkcode", code.toupper())); } #endregion #region 验证码长度(默认4个验证码的长度) int length = 4; public int length { get { return length; } set { length = value; } } #endregion #region 验证码字体大小(为了显示扭曲效果，默认40像素，可以自行修改) int fontsize = 22; public int fontsize { get { return fontsize; } set { fontsize = value; } } #endregion #region 边框补(默认1像素) int padding = 2; public int padding { get { return padding; } set { padding = value; } } #endregion #region 是否输出燥点(默认不输出) bool chaos = true; public bool chaos { get { return chaos; } set { chaos = value; } } #endregion #region 输出燥点的颜色(默认灰色) color chaoscolor = color.lightgray; public color chaoscolor { get { return chaoscolor; } set { chaoscolor = value; } } #endregion #region 自定义背景色(默认白色) color backgroundcolor = color.white; public color backgroundcolor { get { return backgroundcolor; } set { backgroundcolor = value; } } #endregion #region 自定义随机颜色数组 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; } } #endregion #region 自定义字体数组 string[] fonts = { "arial", "georgia" }; public string[] fonts { get { return fonts; } set { fonts = value; } } #endregion #region 自定义随机码字符串序列(使用逗号分隔) string codeserial = "0,1,2,3,4,5,6,7,8,9,a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z,a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z"; public string codeserial { get { return codeserial; } set { codeserial = value; } } #endregion #region 产生波形滤镜效果 private const double pi = 3.1415926535897932384626433832795; private const double pi2 = 6.283185307179586476925286766559; /// <summary> /// 正弦曲线wave扭曲图片 /// </summary> /// <param name="srcbmp">图片路径</param> /// <param name="bxdir">如果扭曲则选择为true</param> /// <param name="nmultvalue">波形的幅度倍数，越大扭曲的程度越高，一般为3</param> /// <param name="dphase">波形的起始相位，取值区间[0-2*pi)</param> /// <returns></returns> public bitmap twistimage(bitmap srcbmp, bool bxdir, double dmultvalue, double dphase) { bitmap destbmp = new bitmap(srcbmp.width, srcbmp.height); // 将位图背景填充为白色 system.drawing.graphics graph = graphics.fromimage(destbmp); graph.fillrectangle(new solidbrush(color.white), 0, 0, destbmp.width, destbmp.height); graph.dispose(); double dbaseaxislen = bxdir ? (double)destbmp.height : (double)destbmp.width; for (int i = 0; i < destbmp.width; i++) { for (int j = 0; j < destbmp.height; j++) { double dx = 0; dx = bxdir ? (pi2 * (double)j) / dbaseaxislen : (pi2 * (double)i) / dbaseaxislen; dx += dphase; double dy = math.sin(dx); // 取得当前点的颜色 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 < destbmp.width && noldy >= 0 && noldy < destbmp.height) { destbmp.setpixel(noldx, noldy, color); } } } return destbmp; } #endregion #region 生成校验码图片 public bitmap createimagecode(string code) { int fsize = fontsize; int fwidth = fsize + padding; int imagewidth = (int)(code.length * fwidth) + 4 + padding * 2; int imageheight = fsize * 2 + padding; system.drawing.bitmap image = new system.drawing.bitmap(imagewidth, imageheight); graphics g = graphics.fromimage(image); g.clear(backgroundcolor); random rand = new random(); //给背景添加随机生成的燥点 if (this.chaos) { pen pen = new pen(chaoscolor, 0); int c = length * 10; for (int i = 0; i < c; i++) { int x = rand.next(image.width); int y = rand.next(image.height); g.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 f; brush b; int cindex, findex; //随机字体和颜色的验证码字符 for (int i = 0; i < code.length; i++) { cindex = rand.next(colors.length - 1); findex = rand.next(fonts.length - 1); f = new system.drawing.font(fonts[findex], fsize, system.drawing.fontstyle.bold); b = new system.drawing.solidbrush(colors[cindex]); if (i % 2 == 1) { top = top2; } else { top = top1; } left = i * fwidth; g.drawstring(code.substring(i, 1), f, b, left, top); } //画一个边框 边框颜色为color.gainsboro g.drawrectangle(new pen(color.gainsboro, 0), 0, 0, image.width - 1, image.height - 1); g.dispose(); //产生波形（add by 51aspx.com） image = twistimage(image, true, 4, 4); return image; } #endregion #region 将创建好的图片输出到页面 public void createimageonpage(string code, httpcontext context) { response.bufferoutput = true; //特别注意 response.cache.setexpires(datetime.now.addmilliseconds(-1));//特别注意 response.cache.setcacheability(httpcacheability.nocache);//特别注意 response.appendheader("pragma", "no-cache"); //特别注意 memorystream ms = new memorystream(); bitmap image = this.createimagecode(code); image.save(ms, imageformat.jpeg); response.clearcontent(); response.contenttype = "image/jpeg"; response.binarywrite(ms.toarray()); response.end(); ms.close(); ms = null; image.dispose(); image = null; } #endregion #region 生成随机字符码 public string createverifycode(int codelen) { if (codelen == 0) { codelen = length; } string[] arr = codeserial.split(','); string code = ""; int randvalue = -1; random rand = new random(unchecked((int)datetime.now.ticks)); for (int i = 0; i < codelen; i++) { randvalue = rand.next(0, arr.length - 1); code += arr[randvalue]; } return code; } public string createverifycode() { return createverifycode(0); } #endregion #region 另一种验证码样式 generateverifyimage(int length) /// <summary> /// 将创建好的图片输出到页面 /// </summary> public void generateverifyimage(int nlen) { string validatecode = "";//生成的验证码 int nbmpwidth = getimagewidth(nlen); int nbmpheight = getimageheight(); system.drawing.bitmap bmp = new system.drawing.bitmap(nbmpwidth, nbmpheight); //对图像进行弯曲 twistimage(bmp, true, 12, 2); // 1. 生成随机背景颜色 int nred, ngreen, nblue; // 背景的三元色 system.random rd = new random((int)system.datetime.now.ticks); nred = rd.next(255) % 128 + 128; ngreen = rd.next(255) % 128 + 128; nblue = rd.next(255) % 128 + 128; // 2. 填充位图背景 system.drawing.graphics graph = system.drawing.graphics.fromimage(bmp); graph.fillrectangle(new solidbrush(system.drawing.color.fromargb(nred, ngreen, nblue)) , 0 , 0 , nbmpwidth , nbmpheight); // 3. 绘制干扰线条，采用比背景略深一些的颜色 int nlines = 3; system.drawing.pen pen = new system.drawing.pen(system.drawing.color.fromargb(nred - 17, ngreen - 17, nblue - 17), 2); for (int a = 0; a < nlines; a++) { int x1 = rd.next() % nbmpwidth; int y1 = rd.next() % nbmpheight; int x2 = rd.next() % nbmpwidth; int y2 = rd.next() % nbmpheight; graph.drawline(pen, x1, y1, x2, y2); } // 采用的字符集，可以随即拓展，并可以控制字符出现的几率 string strcode = "0123456789abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz"; // 4. 循环取得字符，并绘制 for (int i = 0; i < nlen; i++) { int x = (i * 13 + rd.next(3)); int y = rd.next(4) + 1; // 确定字体 system.drawing.font font = new system.drawing.font("courier new",//文字字体类型 12 + rd.next() % 4,//文字字体大小 system.drawing.fontstyle.bold);//文字字体样式 char c = strcode[rd.next(strcode.length)]; // 随机获取字符 validatecode += c.tostring(); // 绘制字符 graph.drawstring(c.tostring(), font, new solidbrush(system.drawing.color.fromargb(nred - 60 + y * 3, ngreen - 60 + y * 3, nblue - 40 + y * 3)), x, y); } session["validatecode"] = validatecode; //对图像进行弯曲 twistimage(bmp, true, 4, 4); response.bufferoutput = true; //特别注意 response.cache.setexpires(datetime.now.addmilliseconds(-1));//特别注意 response.cache.setcacheability(httpcacheability.nocache);//特别注意 response.appendheader("pragma", "no-cache"); //特别注意 // 5. 输出字节流 memorystream bstream = new memorystream(); bmp.save(bstream, imageformat.jpeg); response.clearcontent(); response.contenttype = "image/jpeg"; response.binarywrite(bstream.toarray()); response.end(); bstream.close(); bstream = null; bmp.dispose(); bmp = null; graph.dispose(); } ///<summary> ///得到验证码图片的宽度 ///</summary> ///<paramname="validatenumlength">验证码的长度</param> ///<returns></returns> public static int getimagewidth(int validatenumlength) { return (int)(13 * validatenumlength + 5); } ///<summary> ///得到验证码的高度 ///</summary> ///<returns></returns> public static int getimageheight() { return 25; } #endregion }
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