发布：2022/6/2 20:22:07作者：管理员 来源：本站 浏览次数：1377
生成图像文件类（添加NuGet包：ZKWeb.System.Drawing）
using System;
using System.DrawingCore;
using System.DrawingCore.Imaging;
using System.IO;
namespace Security
{
public static class VierificationCodeServices
{
/// <summary>
/// 该方法用于生成指定位数的随机数
/// </summary>
/// <param name="VcodeNum">参数是随机数的位数</param>
/// <returns>返回一个随机数字符串</returns>
private static string RndNum(int VcodeNum)
{
//验证码可以显示的字符集合
string Vchar = "0,1,2,3,4,5,6,7,8,9,a,b,c,d,e,f,g,h,i,j,k,l,m,n,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,P,P,Q" +
",R,S,T,U,V,W,X,Y,Z";
string[] VcArray = Vchar.Split(new Char[] { ',' });//拆分成数组
string code = "";//产生的随机数
int temp = -1;//记录上次随机数值，尽量避避免生产几个一样的随机数
Random rand = new Random();
//采用一个简单的算法以保证生成随机数的不同
for (int i = 1; i < VcodeNum + 1; i++)
{
if (temp != -1)
{
rand = new Random(i * temp * unchecked((int)DateTime.Now.Ticks));//初始化随机类
}
int t = rand.Next(61);//获取随机数
if (temp != -1 && temp == t)
{
return RndNum(VcodeNum);//如果获取的随机数重复，则递归调用
}
temp = t;//把本次产生的随机数记录起来
code += VcArray[t];//随机数的位数加一
}
return code;
}
/// <summary>
/// 该方法是将生成的随机数写入图像文件
/// </summary>
/// <param name="code">code是一个随机数</param>
/// <param name="numbers">生成位数（默认4位）</param>
public static MemoryStream Create(out string code, int numbers = 4)
{
code = RndNum(numbers);
Bitmap Img = null;
Graphics g = null;
MemoryStream ms = null;
Random random = new Random();
//验证码颜色集合
Color[] c = { Color.Black, Color.Red, Color.DarkBlue, Color.Green, Color.Orange, Color.Brown, Color.DarkCyan, Color.Purple };
//验证码字体集合
string[] fonts = { "Verdana", "Microsoft Sans Serif", "Comic Sans MS", "Arial", "宋体" }; //定义图像的大小，生成图像的实例
Img = new Bitmap((int)code.Length * 18, 32);
g = Graphics.FromImage(Img);//从Img对象生成新的Graphics对象
g.Clear(Color.White);//背景设为白色
//在随机位置画背景点
for (int i = 0; i < 100; i++)
{
int x = random.Next(Img.Width);
int y = random.Next(Img.Height);
g.DrawRectangle(new Pen(Color.LightGray, 0), x, y, 1, 1);
}
//验证码绘制在g中
for (int i = 0; i < code.Length; i++)
{
int cindex = random.Next(7);//随机颜色索引值
int findex = random.Next(5);//随机字体索引值
Font f = new Font(fonts[findex], 15, FontStyle.Bold);//字体
Brush b = new SolidBrush(c[cindex]);//颜色
int ii = 4;
if ((i + 1) % 2 == 0)//控制验证码不在同一高度
{
ii = 2;
}
g.DrawString(code.Substring(i, 1), f, b, 3 + (i * 12), ii);//绘制一个验证字符
}
ms = new MemoryStream();//生成内存流对象
Img.Save(ms, ImageFormat.Jpeg);//将此图像以Png图像文件的格式保存到流中
//回收资源
g.Dispose();
Img.Dispose();
return ms;
}
}
}
|
controller（添加NuGet包：Microsoft.AspNetCore.Session）（谷歌浏览器跨域需要设置用户客户端，不建议使用session存储方案）
using System.Threading.Tasks;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Cors;
using Security;
namespace Back
{
[Route("back/[controller]/[action]"), EnableCors("AllowAnyOrigin")]
public class LoginController : Controller
{
/// <summary>
/// 后台登入系统
/// </summary>
[HttpGet]
public async Task<IActionResult> Login(string pPhone, string pPassword, string code)
{
string loginValidateCode = HttpContext.Session.GetString("LoginValidateCode");
if (string.IsNullOrEmpty(code))
{
return BadRequest("请填写验证码");
}
if (code.ToLower() != loginValidateCode.ToLower())
{
return BadRequest("验证码错误");
}
return Ok();
}
/// <summary>
/// 图形验证码
/// </summary>
[HttpGet]
public IActionResult ValidateCode()
{
string code = "";
System.IO.MemoryStream ms = VierificationCodeServices.Create(out code);
HttpContext.Session.SetString("LoginValidateCode", code);
return File(ms.ToArray(), @"image/png");
}
}
}
|
// This method gets called by the runtime. Use this method to add services to the container.
public void ConfigureServices(IServiceCollection services)
{
services.AddMvc();
//添加session
services.AddSession();
//添加跨域访问
services.AddCors(options =>
options.AddPolicy("AllowAnyOrigin",
builder => builder.WithOrigins("*").AllowAnyMethod().AllowAnyHeader().AllowAnyOrigin().AllowCredentials()));
}
// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
public void Configure(IApplicationBuilder app, IHostingEnvironment env)
{
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
//使用Session，必须在UseMvc之上
app.UseSession();
app.UseMvc();
//使用静态文件
app.UseStaticFiles();
}
|
<img :src="codeUrl+'/Login/ValidateCode'" alt="看不清？点击更换" onclick="this.src = this.src + '?'" />
//axios配置
//webapi和vue不同域，由于同源策略，需配置以下代码
axios.defaults.withCredentials=true;
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