html5 required validator not working with input type=button

问题

Here is my html code

<form id="form1" runat="server">
<input id="q" required />
<input id="btn" type="submit" value="Search">
</form>

I have used html5 required field validators, it works but with a post back. so modified the code as follows to avoid postback

<form id="form1" runat="server">
<input id="q" required />
<input id="btn" type="button" value="Search">
</form>

But the required validator doesn't work

回答1:

That's because the required validator is only called on submit, and the type=button is not a submit. Try this (http://jsfiddle.net/upgradellc/vrTLw/):

<form id="form1" runat="server">
    <input id="q" required />
    <input id="btn" type="submit" value="Search">
</form>

来源：https://stackoverflow.com/questions/17163023/html5-required-validator-not-working-with-input-type-button