RegularExpression

sankeerth m

Hi all i am trying to allow alphanumeric and underscore on keypress event. it should not allow any spaces and special characters.It should accept only aphanumeric and underscore please help me out Thanks in advance.

4 Replies

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Jignesh Kumar6y ago
Accepted answer
Hi Sankeerth,

Please find below code which will help you,
<%--  HTML Code start--%>
    "text" id="txtAlphaNumeric" onkeypress="return validateKeypress(alphanumeric);"/>


    <%--  HTML Code End--%>
    <%--  Javascript Code start--%>
    "text/javascript">
        var alphanumeric = /^[a-zA-Z0-9_]*$/;

        function validateKeypress(validChars) {
            var keyChar = String.fromCharCode(event.which || event.keyCode);
            return validChars.test(keyChar) ? keyChar : false;
        }


     <%--  Javascript Code End--%>
+1
sankeerth m6y ago
Thanks a lot Jignesh Kumar . I hope to keep posting like this please respond
+1
Laxmidhar Sahoo6y ago
1. function alphanumeric(inputtxt)
2. {
3. var letters = /^[0-9a-zA-Z]+$/;
4. if(inputtxt.value.match(letters))
5. {
6. alert('true');
7. return true;
8. }
9. else
10. {
11. alert('Please input alphanumeric characters only');
12. return false;
13. }
14. }
0

Rajanikant Hawaldar6y ago

Try this string pattern = "^[a-zA-Z0-9_]*$";