I am trying to create a google web map using google maps v3, and I want to include a function whereby when the user selects a time (e.g. 6AM) in a select option (dropdown list), the markers fitting this condition will appear. However, when I try this, google chrome's console only detects the default selected option and doesn't change the value as selected accordingly. (you can say it doesn't do a postback I suppose?) I looked around and found a solution from this question, and added the codes in accordingly
<select id="ddlTime" onchange="this.form.submit()"> ...
but this is what was returned in my console
Uncaught TypeError: Cannot read property 'submit' of null