How to use grails withForm through ajax call

Question

I am using grails 2.5.2 version. I have a form submit event by ajax call where sometimes form is submitted multiple times. I have goggled for it and see about grails withForm topic. I tried to implement it but it stops the request for the first time and show invalid token message. How can I use useToken for withForm or other way to stop multiple time form submit via ajax call in grails.

My code attempts are below.

My ajax call:

jQuery.ajax({
                    type: 'POST',
                    dataType:'JSON',
                    data: $("#createFormModal").serialize(),
                    url: "${g.createLink(controller: 'studentCollection', action: 'save')}",
                    success: function (data) {
                        if(data.isError==true){
                            showAlertModal(data.message);
                        }else {
                            $('#createModal').modal('hide');
                            $('#list-table').DataTable().ajax.reload();
                            showSuccessMsg(data.message);
                            $("#createFormModal").find("input[type=text], textarea").val("");
                        }
                    },
                    error: function (XMLHttpRequest, textStatus, errorThrown) {
                    }
                });

My controller method:

def save() {
    LinkedHashMap result = new LinkedHashMap()
    String outPut

    withForm {
        result = studentCollectionService.saveCollection(params)
    }.invalidToken {
        println("### invalidate Token")
        result.put(CommonUtils.IS_ERROR, Boolean.TRUE)
        result.put(CommonUtils.MESSAGE, "Please press the button once")
    }

    outPut = result as JSON
    render outPut
    return
}