taking input from button in thymeleaf - html

Question

I am displaying a form to user with some details and then user clicks approve and reject. In the backend, I want to take this in one property - userAction, which can be "approve" or "reject".
How can I add input to the buttons that user clicks? And then this input is part of the object requestDto.
<form th:action="#{/mission/store/{uuid}(uuid=${uuid})}" th:object="${requestDto}" method="post" class="mission_form">
<div class="wizard-header">
<h3 class="wizard-title">
Approve Mission
</h3>
<h5>Should you chose to accept this mission, press approve.</h5>
</div>
<div class="wizard-footer">
<!--<div class="pull-right">-->
<input type='button' class="btn btn-success" name='approve' value='Approve' />
<!--</div>-->
<div class="pull-left">
<input type='button' th:field="*{}" class='btn btn-danger' name='previous' value='Decline' />
</div>
<div class="clearfix"></div>
</div>
</form>

Answer 1

First define a proper DataTransferObject:
public class MyRequestDto {
private String userAction;
// don't forget getters and setters
}
Then add a object of that class to your model
// if you are return a M&V-object:
ModelAndView mv = new ModelAndView("viewName")
ModelAndView.addObject("requestDto", new MyRequestDto());
// if you define a Model-Object as input-parameter:
Model.addAttribute("requestDto", new MyRequestDto());
Define a form like this (I used button-elements). The point is not to use the th:field attribute:
<form th:action="...." method="POST" th:object="${requestDto}">
<button name="userAction" value="approve" >Approve</button>
<button name="userAction" value="reject" >Reject</button>
</form>
Recieve the DataTransferObject by adding this to your controllers input-paramters (the controller that handels the post request):
... #Valid RequestDto requestDto, BindingResult bindingResult, ....
Now you can access requestDto's userAction-Attribute. The value is approve if you click the first button and it is reject if you click the second button. First you can check if there are binding errors by checking bindingResults.hasErrors().