How to restrict user input for entering only one number using scanner object

Question

0.00/5 (No votes)

See more:

Scanner sc = new Scanner(System.in);
int tosend = sc.nextInt();

I want that user should be able to only enter any one number, after that scanner object should be stopped but i don't want to close this object because i need it later.

What I have tried:

I tried to restrict for entering only one number using flag variable but didnt worked.

Posted 17-Jul-20 21:13pm

nitinjain9619

Updated 17-Jul-20 22:09pm

Richard MacCutchan

v3

Add a Solution

Comments

Richard MacCutchan 18-Jul-20 4:10am

It is not difficult to write code that only calls nextInt once. What exactly did you try?

nitinjain9619 18-Jul-20 4:43am

i was trying wrong i created variable int flag=1 and then before reading user input i was checking flag is 1 if yes then allow to write using sc.nextInt(); and after that flag=0;

Richard MacCutchan 18-Jul-20 4:53am

Why do you need a flag at all? Just call nextInt once to capture the user's input. You do not need to call it again. But you really need to show your code and explain more clearly exactly what you are trying to do.

nitinjain9619 18-Jul-20 5:10am

actually i want that if user enter for first than it should be allowed, after that scanner object should not store anything (after enter key pressed).
i am working on a project bingo game where each player will get chance circularly,my code is working perfect if user enter one number at a time but whenever he enter two number simultaneously then at next chance whatever he written 2nd time in his previous chance is considering his played number in current chance i want to stop user for entering two number simultaneously.

and thanks for your support..

Richard MacCutchan 18-Jul-20 5:24am

I gave you a suggestion 4 days ago at How to give chance to all clients one by one to send a number and block a client to send number if its not his chance in socket java program.[^].

nitinjain9619 18-Jul-20 5:31am

yes,i applied it and it is working fine now but now i want that scanner object should not store any thing after enter key pressed it should store only first number and stop reading after that. Is it possible?

Richard MacCutchan 18-Jul-20 5:55am

The scanner will only read what you tell it to read. And it will only store what you tell it to store.

nitinjain9619 18-Jul-20 6:01am

I am very touched by what you have done for me and thank you so much once again

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)