来自类的Jquery输入ID

我有：

<div class="buttons">   

<input id = "previous" class="previous_button" type="submit" 
style="margin-right: 10px;" value="Previous"/>

<input id = "next" class="next_button" type="submit" 
style="margin-right: 10px;" value="Next"/>

</div>

活动代表团

$('.buttons').on('click', 'input[type=submit]', function(e) {
    alert(this.id);
});

$('.buttons').on('click', 'input[type=submit]', function(e) {
    alert(this.id);
});