点击生成动态验证码(工具类)

喜欢ヅ旅行 2022-05-15 15:51 235阅读 0赞

## 1.页面 ##

<div class="col-sm-3">
    				<img id="vcode" src="/checkCode" style="cursor:pointer">
    			</div>
    	
    	
    			<script type="text/javascript"> $("#vcode").click(function(){ $(this).attr("src" , "/checkCode?t=" + new Date()); }); </script>

//触发图片的点击事件
      $("#vcode").click();

## 2.后台controller ##

package com.czxy.controller;
    
    import org.springframework.http.HttpStatus;
    import org.springframework.http.ResponseEntity;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RestController;
    
    import javax.imageio.ImageIO;
    import javax.servlet.http.HttpServletResponse;
    import javax.servlet.http.HttpSession;
    import java.awt.*;
    import java.awt.image.BufferedImage;
    import java.io.OutputStream;
    import java.util.Random;
    
    
    @RestController
    public class CheckCodeController { 
    
        @RequestMapping("checkCode")
        public ResponseEntity<Void> checkCode(HttpServletResponse response, HttpSession session){ 
            try { 
                int width = 80;
                int height = 32;
                //create the image
                BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
                Graphics g = image.getGraphics();
                // set the background color
                g.setColor(new Color(0xDCDCDC));
                g.fillRect(0, 0, width, height);
                // draw the border
                g.setColor(Color.black);
                g.drawRect(0, 0, width - 1, height - 1);
                // create a random instance to generate the codes
                Random rdm = new Random();
                String hash1 = Integer.toHexString(rdm.nextInt());
                // make some confusion
                for (int i = 0; i < 50; i++) { 
                    int x = rdm.nextInt(width);
                    int y = rdm.nextInt(height);
                    g.drawOval(x, y, 0, 0);
                }
                // generate a random code
                String capstr = hash1.substring(0, 4);
                session.setAttribute("validateCode", capstr);
                g.setColor(new Color(0, 100, 0));
                g.setFont(new Font("Candara", Font.BOLD, 24));
                g.drawString(capstr, 8, 24);
                g.dispose();
                response.setContentType("image/jpeg");
                OutputStream strm = response.getOutputStream();
                ImageIO.write(image, "jpeg", strm);
                strm.close();
    
                return ResponseEntity.ok().build();
            } catch (Exception e){ 
                e.printStackTrace();
    
                return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).build();
            }
        }
    }