You have some syntax errors and you probably don't want to use hide(), just clear the HTML for #tagErrorMsg
. Have a look at this example - http://jsfiddle.net/jayblanchard/mqeCj/
$('#uTagNum').blur(function () {
var tagNumber = $(this).val();
console.log(tagNumber);
if (tagNumber.length < 9) {
$('#tagErrorMsg').html('<div>Invalid format.Hover over Tag Number column name to see valid formats</div>');
} else {
$('#tagErrorMsg').html('');
}
});