//验证码
public String imageCode() throws IOException{
//获得验证码随机数
String code = ImageUtil1.getRandomCode(4);
BufferedImage img = ImageUtil1.createImage(code);
ValueStackUtil.setSessionAttribute("imgCode", code);
ImageIO.write(img, "png", ServletActionContext.getResponse().getOutputStream());
return null;
}
点击验证码变换
<tr>
<td valign="middle" align="right">
验证码:
<img id="num" src="<s:url value='/user/user_imageCode'/>" οnclick='this.src=this.src+"?c="+Math.random()'/>
</td>
<td valign="middle" align="left">
<input id="code" type="text" required="true" class="inputgri" name="code" />
</td>
</tr>
点击换一张更换验证码
<script type="text/javascript">
function fun(){
var img1 = document.getElementById("num");
img1.src = "<s:url value='/user/user_imageCode'/>;" + new Date();
}
</script>
<tr>
<td valign="middle" align="right">
验证码:
<img id="num" src="<s:url value='/user/user_imageCode'/>" />
<a href="javascript:void(0)" οnclick="fun()">换一张</a>
</td>
<td valign="middle" align="left">
<input type="text" class="inputgri" name="code" />
</td>
</tr>
验证码的util方法：
public class ImageUtil {
public static String getRandomCode(int n){
String str = "1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
int len = str.length();
StringBuffer sb = new StringBuffer();
Random r = new Random();
for(int i=0;i<n;i++){
sb.append(str.charAt(r.nextInt(len)));
}
return sb.toString();
}
public static BufferedImage createImage(String securityCode){
int codeLength = securityCode.length();//验证码长度
int fontSize = 20;//字体大小
int fontWidth = fontSize+1;
//图片宽高
int width = codeLength*fontWidth+60;
int height = fontSize*2;
//图片
BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
Graphics2D g = image.createGraphics();
g.setColor(Color.WHITE);//设置背景色
g.fillRect(0, 0, width, height);//填充背景
g.setColor(Color.LIGHT_GRAY);//设置边框颜色
g.setFont(new Font("Courier New", Font.BOLD, height-2));//边框字体样式
g.drawRect(0, 0,0, 0);//绘制边框
//绘制噪点
Random rand = new Random();
g.setColor(Color.LIGHT_GRAY);
for (int i = 0; i < codeLength*6; i++) {
int x = rand.nextInt(width);
int y = rand.nextInt(height);
g.drawRect(x, y, 1, 1);//绘制1*1大小的矩形
}
//绘制验证码
int codeY = height-10;
g.setColor(new Color(19,148,246));
g.setFont(new Font("Georgia", Font.BOLD, fontSize));
for(int i=0;i<codeLength;i++){
double deg=new Random().nextDouble()*20;
g.rotate(Math.toRadians(deg), i*16+13,codeY-7.5);
g.drawString(String.valueOf(securityCode.charAt(i)), i*16+5, codeY);
g.rotate(Math.toRadians(-deg), i*16+13,codeY-7.5);
}
g.dispose();//关闭资源
return image;
}
}
