Validate postcode on keypress
http://stackoverflow.com/questions/27315788/validate-text-input-to-match-canadian-postal-code-e-g-a1s2s3
by Ketan Patel
HTML
<input type="text" id="postCode" placeholder="Enter postcode">
<span id="result"></span>
JavaScript
var pattern = /[a-zA-Z][0-9][a-zA-Z](-| |)[0-9][a-zA-Z][0-9]/,
$result = $("#result");
$('#postCode').keyup(function(){
var val = this.value
if(!val.match(pattern)){
$result.text("invalid");
} else {
$result.text("valid");
}
});