lx010手机号码验证

public static void main(String[] args) {
System.out.println("请输入手机号：");
Scanner scan = new Scanner(System.in);
String str = scan.nextLine();
printNum(str);
System.out.println(printNum(str));
while(printNum(str) !="输入成功"){//此处有多重循环
System.out.println("请重新输入：");
str = scan.nextLine();
System.out.println(printNum(str));
}
}
public static String printNum(String str) {
char[] c = str.toCharArray();
for(int i=0;i<c.length;i++){//判断每位是否都为空
if(c[i] < 48 || c[i] > 57){//使用ASCII表进行判断是否0-9
return "格式错误,请重新输入";
}
}
if(c.length != 11){//判断长度是否11
return "号码为11位,请重新输入";
}
else if(c[0] == 49 && (c[1]==51 || c[1]==53) && (c[2] == 56 || c[2] == 57)){//判断第一二三位是否合格
return "输入成功";
}
else {
return "格式错误,请重新输入";
}
}