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Thread: Input Validation - Take no Symbols or Numbers

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    Default Input Validation - Take no Symbols or Numbers

    So what I'm trying to do is take String input and validation to the following correspondences:

    1. Take no Digits "1234567890"
    2. Take no Symbols/Special Characters "!@$%^&*()"

    OUTPUT FROM TESTING FOLLOWING CODE:

    Please enter your name:
    John Smith2323
    Found a special character
    Name: J Smith2323

    So... The program has detected a special character, or a digit. So it printed "Found Special Character..."... So my code is half way there...

    What I need to do, is detect the special character, and if this is detected then it should ask for the input again. It will keep asking for the input until the input has only a letter values and a whitespace.

    I might need a loop in here somewhere, but I am not sure where I should put it... or how to structure it... maybe some boolean values as well?

    System.out.println("Please enter your name: ");
                n = kbd.nextLine(); 
               char[] chars = n.toCharArray();
               boolean sChar = false;
               for(char c : chars) {
                   if(!Character.isLetter(c) && (!Character.isWhitespace(c))) {
                       sChar = true;
                       }
                   }
                   if(sChar == true) {
                       System.out.println("Found a special character");
                   }


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    Default Re: Input Validation - Take no Symbols or Numbers

    Do it on a while loop until your validation is successful you must keep taking input.

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    Default Re: Input Validation - Take no Symbols or Numbers

    Not very helpful. I already know I need a while loop. But, I just don't know where it should be, or how it should be structured≈...

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    Default Re: Input Validation - Take no Symbols or Numbers

    Why don't you use Java Regular Expression ?

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    Default Re: Input Validation - Take no Symbols or Numbers

    I think a Do-While loop will be a good start!
    Since your program is going to have to test the name every time it is entered it ought to be in the loop body, and the do-while allows for a post-loop-coninuation-testing. Maybe you can figure out what the loop continuation condition will be.

    do
    {loop body}
    while (loop-continuation-condition)

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