生成随机数
private String generateCode() { int min = 100000; int max = 1000000;
Random rand = new Random();
int res = this.rand.nextInt(max - min) + min; return String.valueOf(res); }
private String generateCode() { int min = 100000; int max = 1000000;
Random rand = new Random();
int res = this.rand.nextInt(max - min) + min; return String.valueOf(res); }