验证码是指网页的验证码还是手机的验证码
下面是随机生成四位数的相关代码
import java.util.Random;
public class RandomTest {
public static void main(String[] args) {
System.out.println("Math.random得到小数");
System.out.println(Math.round(Math.random() * 10000));
System.out.println("Random");
System.out.println(new Random().nextInt(9999));
System.out.println("字符串前面补0的话就这样String.format");
System.out.println(String.format("%04d",new Random().nextInt(9999)));
}
}
public static void main(String[] args){
Random d = new Random();
String str = "";
for(int i=0;i<4;i++){
int num = d.nextInt(10);
str += num+"";
}
System.out.println(str);
}
希望能帮到你
for (int i = 0; i < 4; i++) {
System.err.print((int) (Math.random() * 10));
}
Random取1-9,再取3次0-9