CODEWITHSUNDEEP
javagwt
WelcomeTo
WelcomeTo

Reputation: 20581

How to allow user to enter only the letters, no numbers and other characters

I want to implement a TexBox where the user can input only letters. When the user enter numbers or invalid characters, an error message must show near by. Like this:

enter image description here

Upvotes: 7

Views: 5254

Answers (4)

Jama A.
Jama A.

Reputation: 16089

You can use Character.isLetter(char) on TextBox's KeyUpHandler: 

  textBox.addKeyUpHandler(new KeyUpHandler() {
            public void onKeyUp(KeyUpEvent event) {
                if (!Character.isLetter(event.getNativeKeyCode())) {
                    ((TextBox)event.getSource()).cancelKey();
                    customPopup.showRelativeTo(textBox);// your styled PopupPanel
                }
            }
        });

But, Character.isLetter(char) works with ASCII, if you want more see you can do it something like that:

/**
     * A better implementation of isLetter -- the default GWT version doesn't 
     * support non-English characters.
     *
     * @param c the character to check
     * @return whether the character represents and alphabetic symbol.
     */
    public static boolean isLetter(char c) {
        int val = (int) c;

        return inRange(val, 65, 90) || inRange(val, 97, 122) || inRange(val, 192, 687) || inRange(val, 900, 1159) ||
        inRange(val, 1162, 1315) || inRange(val, 1329, 1366) || inRange(val, 1377, 1415) || inRange(val, 1425, 1610);
    }

    /**
     * Checks if an int value is in a range.
     * @param value value to check
     * @param min min value
     * @param max max value
     * @return whether value is in the range, inclusively.
     */
    public static boolean inRange(int value, int min, int max) {
        return (value <= max) & (value >= min);
    }

See this: http://code.google.com/p/google-web-toolkit/issues/detail?id=1983

Upvotes: 9

Kushan
Kushan

Reputation: 10695

Javascript to allow Alphabetical characters 

function AllowAlphabet(e)
{

   keyEntry = !isIE ? e.which : event.keyCode;
   if (((keyEntry >= '65') && (keyEntry <= '90')) || ((keyEntry >= '97') && (keyEntry <= 
   '122')) || (keyEntry == '46') || (keyEntry == '32') || keyEntry == '45')
   return true;
}

Upvotes: 1

Sankalp
Sankalp

Reputation: 2086

You may add regex to do this

Upvotes: 1

gprathour
gprathour

Reputation: 15333

You can write some validation code on keyTyped event to check, what was the last letter typed. Was it a number or not. If not then show error message.

Try considering KeyLister method : keyTyped()

Upvotes: 1

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