Checkboxes type to NULL

Question

Can the checkboxes field type can be made to NULL if none of the options is selected for a filed For example: I have four checkboxes for a field in my form and initially one was checked later all were unchecked can the field be made NULL?

SanfordWhiteman · Accepted Answer

Add a checkbox with the literal string value NULL.

Hide it by default:

.mktoForm .mktoCheckboxList input[value="NULL"],
.mktoForm .mktoCheckboxList input[value="NULL"] + label {
	display: none;
}

If the value is empty on submit, then flip it to NULL.

MktoForms2.whenReady(function(readyForm){
  readyForm.onSubmit(function(submittingForm){
    const currentValues = submittingForm.getValues();
    if(currentValues.MyInterestingField == "") {
      submittingForm.setValeus({
         MyInterestingField : "NULL"
      });
    });
  });
});