使用方法参数的Java验证
我正在尝试使用验证方法验证Signin()和Signup()的用户名和密码字段。现在,当我输入正确的用户名时,它会不断显示错误,我不知道为什么 验证方法:使用方法参数的Java验证,java,validation,Java,Validation,我正在尝试使用验证方法验证Signin()和Signup()的用户名和密码字段。现在,当我输入正确的用户名时,它会不断显示错误,我不知道为什么 验证方法: void signup_username_validation(String username) //Username validation for signup { String user_name = ""; if(user_name.length() < 6 || user_name.length() >
void signup_username_validation(String username) //Username validation for signup
{
String user_name = "";
if(user_name.length() < 6 || user_name.length() > 15)
{
System.out.println("Username cannot be less then 6 and greater then 15 characters");
Signup();
}
}
void signup_password_validation(String password) //Password validation for signup
{
String pass = "";
if(pass.length() < 6)
{
System.out.println("Password cannot be less then 6 characters");
Signup();
}
}
您正在分配给
String user_name=”“
并检查此始终为空的值即检查新创建变量的有效性,您已将其初始化为空字符串。您真正想做的是检查方法参数的有效性
void signup_username_validation(String username) //Username validation for signup
{
if(username.length() < 6 || username.length() > 15)
{
System.out.println("Username cannot be less then 6 and greater then 15 characters");
Signup();
}
}
void signup_password_validation(String password) //Password validation for signup
{
if(password.length() < 6)
{
System.out.println("Password cannot be less then 6 characters");
Signup();
}
}
void signup\u username\u验证(字符串username)//注册的用户名验证
{
if(username.length()<6 | | username.length()>15)
{
System.out.println(“用户名不能少于6个字符,不能超过15个字符”);
注册();
}
}
无效注册\密码\验证(字符串密码)//注册的密码验证
{
if(password.length()<6)
{
System.out.println(“密码不能少于6个字符”);
注册();
}
}
试试看
公共类测试{
无效注册\用户名\验证(字符串用户名)//注册的用户名验证
{
//字符串user_name=“”;
if(user_name.length()<6|user_name.length()>15)
{
System.out.println(“用户名不能少于6个字符,不能超过15个字符”);
注册();
}
}
私人无效注册(){
//TODO自动生成的方法存根
}
无效注册\密码\验证(字符串传递)//注册的密码验证
{
//字符串pass=“”;
if(pass.length()<6)
{
System.out.println(“密码不能少于6个字符”);
注册();
}
}
}
他对密码做了同样的操作。它要求初始化。那么我应该如何初始化变量user_name?使用username param variable而不是创建新的user_name(同时检查null)@Jeff Craine您传入了username
变量,但从未使用过它。然后您创建了另一个user\u name
变量并使用了该变量而不是键盘.next()代码>如果您希望用户在完成键入时按enter键。
void signup_username_validation(String username) //Username validation for signup
{
if(username.length() < 6 || username.length() > 15)
{
System.out.println("Username cannot be less then 6 and greater then 15 characters");
Signup();
}
}
void signup_password_validation(String password) //Password validation for signup
{
if(password.length() < 6)
{
System.out.println("Password cannot be less then 6 characters");
Signup();
}
}
public class Test {
void signup_username_validation(String user_name) //Username validation for signup
{
// String user_name = "";
if(user_name.length() < 6 || user_name.length() > 15)
{
System.out.println("Username cannot be less then 6 and greater then 15 characters");
Signup();
}
}
private void Signup() {
// TODO Auto-generated method stub
}
void signup_password_validation(String pass) //Password validation for signup
{
// String pass = "";
if(pass.length() < 6)
{
System.out.println("Password cannot be less then 6 characters");
Signup();
}
}
}