Question

Is there a way that I can change the values put in the param map from checkboxes? I’ve noticed that elements with a checkbox will either have a value of “on” in the param map if the checkbox was checked or there will be an underscore preceding the element name as a key in the param map with a value of “” if the checkbox was not checked. Is there any way I can change this behavior so that a value of “true” will be in the param map if checked and a value of “false” (preferably without the ‘_’ preceding the element’s name) if the box was not checked?

Answer 1

GSP Form

<g:form controller="test" action="testForm">
  <g:checkBox name="box" value="${true}" />
  <g:submitButton name="submit" value="submit" />
</g:form>

Controller Code

def testForm() {
  println params.box as boolean
}

Output

true // when box checked
false // when box unchecked