<script type="text/javascript">
    // This function is being used for providing different validation on your text box as per your need
    function ValidatedField(e, allow) {

        var AllowableCharacters = '';

        if (allow == 'Letters') {
            AllowableCharacters = ' ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz';
        }
        if (allow == 'Numbers') {
            AllowableCharacters = '1234567890';
        }
        if (allow == 'NameCharacters') {
            AllowableCharacters = ' ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz-.\'';
        }
        if (allow == 'NameCharactersAndNumbers') {
            AllowableCharacters = '1234567890 ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz-\'';
        }
        if (allow == 'Currency') {
            AllowableCharacters = '1234567890.';
        }

        var k = document.all ? parseInt(e.keyCode) : parseInt(e.which);

        if (k != 13 && k != 8 && k != 0) {
            if ((e.ctrlKey == false) && (e.altKey == false)) {
                return (AllowableCharacters.indexOf(String.fromCharCode(k)) != -1);
            } else {
                return true;
            }
        } else {
            return true;
        }
    }
</script>