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Re: How would you do this kind of validatioin checking

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On 9/12/2011 6:12 PM, Thee Chicago Wolf (MVP) wrote:
> Hi all,
>
> So I was wondering what the simplest way to do this kind of validation
> checking would be.
>
> Let's say you're prompting the user for one or the other of the
> following:
>
> A) foo = keyboard.nextInt();
>
> B) bar = keyboard.nextLine();
>
> If the user decides to be a stinker and, for item A), enter a
> character, it'll bomb out because the input type is expecting an Int.
> So you'd have a while loop of some sort (i.e., while (foo.equals("a"
> || "b" || "c"......)) but that would be a LOT of chacaters to check
> against and seems like bad coding.
>
> If I wanted to do validation checking to counter someone purposely
> entering character input where Int is being expected, is there a
> blanket statement that will check through a-z / A-Z or would using
> something like (!foo.equals() to basically say "if the input is
> anything other than Int, keep looping until the user inputs an Int."
>
> And in the case of B), "if the input is anything other than
> characters, keep looping until the user inputs an character." I'm
> guessing something like: while (bar>= 0 || bar<= 0).
>
> So does one just write a method or class that has all the gruntwork in
> it already and call it or is there something quick and dirty that one
> could use?
>
> Still noobing it up but just want to get a better understanding of
> good practices or logic on how to write some tighter code for
> instances like this. Many thanks for any responses.

I think that the real issue is that nobody is going to write anything 
more complicated than a student exercise using the terminal for I/O.

That said you can go at it several ways, for example you could do all 
the input, validate it and ask for the bad parts over again.  Or you 
could use the infinite loop until valid data is presented or exit after 
three tries or something.

-- 

Knute Johnson

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Thread

How would you do this kind of validatioin checking "Thee Chicago Wolf (MVP)" <.@.> - 2011-09-12 20:12 -0500
  Re: How would you do this kind of validatioin checking Knute Johnson <nospam@knutejohnson.com> - 2011-09-12 18:44 -0700
  Re: How would you do this kind of validatioin checking Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-09-12 21:58 -0400
    Re: How would you do this kind of validatioin checking "Thee Chicago Wolf [MVP]" <.@.> - 2011-09-13 08:41 -0500
  Re: How would you do this kind of validatioin checking Roedy Green <see_website@mindprod.com.invalid> - 2011-09-12 21:59 -0700
    Re: How would you do this kind of validatioin checking "Thee Chicago Wolf [MVP]" <.@.> - 2011-09-13 08:44 -0500
      Re: How would you do this kind of validatioin checking Roedy Green <see_website@mindprod.com.invalid> - 2011-09-13 12:27 -0700

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