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Thread: reading a char with SCANNER

  1. #1
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    Default reading a char with SCANNER

    my teacher only teach to read char with system.in.read(),is there any way to read a char with scanner?? and is a String of "a" same as a char of 'a' .


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    Default Re: reading a char with SCANNER

    Hello lotus,

    You can read a char with the Scanner class like this:

    import java.util.Scanner;
     
    public class lotus {
     
        /**
         * JavaProgrammingForums.com
         */
        public static void main(String[] args) {
     
            Scanner sc = new Scanner(System.in);
            String input = sc.next();
     
            char[] myChar;
            myChar = input.toCharArray();
     
            System.out.println(myChar);
        }
     
    }

    The Scanner class doesn't have .nextChar(); unlike .nextDouble(); .nextInt(); etc.

    Basically you use the Scanner class to read in the user input as String and then you need to convert the String to char.
    A char is a single character, a String is ment to be a sequence of characters. String is an full-blown object, a char primitive data type is just two bytes in unicode.

    I never use a char variable nowdays. Always just stick it in a String.
    Please use [highlight=Java] code [/highlight] tags when posting your code.
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    Default Re: reading a char with SCANNER

    That's a problem, though if you want to read in the next char after... It's only going to return the first char of each word

    To read in a single character, you can use the CharArrayReader class or the BufferedReader class. Actually, I think most of Reader's sub classes should be able to read in a single character.
    Last edited by helloworld922; July 28th, 2009 at 10:55 AM.

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    Default Re: reading a char with SCANNER

    why do you use a char[]??? and not char myChar;

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    Default Re: reading a char with SCANNER

    because im at the final stage of my project, i have users input choice of 1 2 or 3 , but if a user inpuuts a non int number like a it gives a error, so if i want to solve these type of problems i have a String choice and then convert it to whatever i want it to be?

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    Default Re: reading a char with SCANNER

    You'd want to make sure you use char[] for your passwords though

    // Json

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    Default Re: reading a char with SCANNER

    Quote Originally Posted by lotus View Post
    why do you use a char[]??? and not char myChar;
    Take a read of this:

    String (Java Platform SE 6)
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