理解C#生成验证码的过程
本文实例为大家介绍了生成验证码的详细过程，供大家参考，具体内容如下
生成验证码的类：
usingSystem;
usingSystem.Collections.Generic;
usingSystem.Drawing;
usingSystem.Text;
namespaceControllers.Core.Util
{
///<summary>
///验证码
///</summary>
publicclassVerifyCodeHelper:AdminBaseController
{
#region变量
///<summary>
///颜色表
///</summary>
privatestaticColor[]colors=newColor[]{
Color.FromArgb(220,20,60),
Color.FromArgb(128,0,128),
Color.FromArgb(65,105,225),
Color.FromArgb(70,130,180),
Color.FromArgb(46,139,87),
Color.FromArgb(184,134,11),
Color.FromArgb(255,140,0),
Color.FromArgb(139,69,19),
Color.FromArgb(0,191,255),
Color.FromArgb(95,158,160),
Color.FromArgb(255,20,147),
Color.FromArgb(255,165,0)};
///<summary>
///字体表
///</summary>
privatestaticstring[]fonts=newstring[]{
"Arial",
"Verdana",
"Georgia",
"黑体"};
///<summary>
///字体大小
///</summary>
privatestaticintfontSize=22;
#endregion
#region生成验证码图片
///<summary>
///生成验证码图片
///</summary>
publicstaticBitmapCreateVerifyCodeBmp(outstringcode)
{
intwidth=120;
intheight=40;
Bitmapbmp=newBitmap(width,height);
Graphicsg=Graphics.FromImage(bmp);
Randomrnd=newRandom();
//背景色
g.FillRectangle(newSolidBrush(Color.White),newRectangle(0,0,width,height));
//文字
StringBuildersbCode=newStringBuilder();
for(inti=0;i<4;i++)
{
stringstr=GetChar(rnd);
Fontfont=GetFont(rnd);
Colorcolor=GetColor(rnd);
g.DrawString(str,font,newSolidBrush(color),newPointF((float)(i*width/4.0),0));
sbCode.Append(str);
}
code=sbCode.ToString();
//噪音线
for(inti=0;i<10;i++)
{
intx1=rnd.Next(bmp.Width);
intx2=rnd.Next(bmp.Width);
inty1=rnd.Next(bmp.Height);
inty2=rnd.Next(bmp.Height);
Penp=newPen(GetColor(rnd),1);
g.DrawLine(p,x1,y1,x2,y2);
}
//扭曲
bmp=TwistImage(bmp,true,3,rnd.NextDouble()*Math.PI*2);
g=Graphics.FromImage(bmp);
//噪点
for(inti=0;i<100;i++)
{
intx1=rnd.Next(bmp.Width);
inty1=rnd.Next(bmp.Height);
Penp=newPen(GetColor(rnd),1);
g.DrawRectangle(p,x1,y1,1,1);
}
//边框
g.DrawRectangle(newPen(newSolidBrush(Color.FromArgb(153,153,153))),newRectangle(0,0,width-1,height-1));
returnbmp;
}
#endregion
#region获取随机字符
///<summary>
///获取随机字符
///</summary>
privatestaticstringGetChar(Randomrnd)
{
intn=rnd.Next(0,61);
if(n<=9)
{
return((char)(48+n)).ToString();
}
elseif(n<=35)
{
return((char)(65+n-10)).ToString();
}
else
{
return((char)(97+n-36)).ToString();
}
}
#endregion
#region获取随机字体
///<summary>
///获取随机字体
///</summary>
privatestaticFontGetFont(Randomrnd)
{
returnnewFont(fonts[rnd.Next(0,fonts.Length)],fontSize,FontStyle.Bold);
}
#endregion
#region获取随机颜色
///<summary>
///获取随机颜色
///</summary>
privatestaticColorGetColor(Randomrnd)
{
returncolors[rnd.Next(0,colors.Length)];
}
#endregion
#region正弦曲线Wave扭曲图片
///<summary>
///正弦曲线Wave扭曲图片（EditBy51aspx.com）
///</summary>
///<paramname="srcBmp">图片路径</param>
///<paramname="bXDir">如果扭曲则选择为True</param>
///<paramname="nMultValue">波形的幅度倍数，越大扭曲的程度越高，一般为3</param>
///<paramname="dPhase">波形的起始相位，取值区间[0-2*PI)</param>
privatestaticSystem.Drawing.BitmapTwistImage(BitmapsrcBmp,boolbXDir,doubledMultValue,doubledPhase)
{
System.Drawing.BitmapdestBmp=newBitmap(srcBmp.Width,srcBmp.Height);
//将位图背景填充为白色
System.Drawing.Graphicsgraph=System.Drawing.Graphics.FromImage(destBmp);
graph.FillRectangle(newSolidBrush(System.Drawing.Color.White),0,0,destBmp.Width,destBmp.Height);
graph.Dispose();
doubledBaseAxisLen=bXDir?(double)destBmp.Height:(double)destBmp.Width;
for(inti=0;i<destBmp.Width;i++)
{
for(intj=0;j<destBmp.Height;j++)
{
doubledx=0;
dx=bXDir?(Math.PI*2*(double)j)/dBaseAxisLen:(Math.PI*2*(double)i)/dBaseAxisLen;
dx+=dPhase;
doubledy=Math.Sin(dx);
//取得当前点的颜色
intnOldX=0,nOldY=0;
nOldX=bXDir?i+(int)(dy*dMultValue):i;
nOldY=bXDir?j:j+(int)(dy*dMultValue);
System.Drawing.Colorcolor=srcBmp.GetPixel(i,j);
if(nOldX>=0&&nOldX<destBmp.Width
&&nOldY>=0&&nOldY<destBmp.Height)
{
destBmp.SetPixel(nOldX,nOldY,color);
}
}
}
returndestBmp;
}
#endregion
}
}
验证码页面Action：
publicActionResultVerifyCode()
{
stringcode;
Bitmapbmp=VerifyCodeHelper.CreateVerifyCodeBmp(outcode);
Bitmapnewbmp=newBitmap(bmp,108,36);
HttpContext.Session["VerifyCode"]=code;
Response.Clear();
Response.ContentType="image/bmp";
newbmp.Save(Response.OutputStream,System.Drawing.Imaging.ImageFormat.Bmp);
returnView();
}
说明：前台页面为空的cshtml页面，验证码的值放在Session中。
使用验证码的页面：
显示验证码的img：
<imgid="verifyCode"src=""alt="验证码"style="vertical-align:middle;"/>
页面加载完成后，显示验证码(注意，要加上时间戳，不然刷新页面时验证码不刷新)：
$(function(){
//刷新验证码
$("#refreshVerifyCode").click(function(){
refreshVerifyCode();//刷新验证码
});
$("#verifyCode").click(function(){
refreshVerifyCode();//刷新验证码
});
refreshVerifyCode();
});
刷新验证码：
//刷新验证码
functionrefreshVerifyCode(){
$("#verifyCode").attr("src","VerifyCode?t="+newDate().valueOf());
}
判断用户输入的文本是否与验证码相同的Action：
publicActionResultCheckVCode(stringvcode)
{
if(HttpContext.Session["VerifyCode"].ToString().ToLower()==vcode.ToLower())
{
Dictionary<string,object>dic=newDictionary<string,object>();
dic["ok"]=true;
returnContent(JsonConvert.SerializeObject(dic));
}
else
{
Dictionary<string,object>dic=newDictionary<string,object>();
dic["ok"]=false;
returnContent(JsonConvert.SerializeObject(dic));
}
}
以上就是本文的全部内容，希望对大家学习C#生成验证码的方法有所帮助。