Spring : Binding (multiple) checkboxes

This page last changed on Jun 19, 2006 by Kees de Kooter

Binding a single checkbox to a form bean

We are using xml compliant JSP so it is a bit verbose . The trick is to add a hidden input tag prefixed with an underscore. Since the browser does not return anything for an unchecked chekbox this way Spring can determine that a checkbox was set to false.

<spring:bind path="acceptDeliveryConditions">
    <input type="hidden" name="_${status.expression}"/>
    <c:choose>
        <c:when test="${status.value == true}">
            <input type="checkbox" name="${status.expression}" 
                checked="checked"/>
        </c:when>
        <c:otherwise>
            <input type="checkbox" name="${status.expression}"/>
        </c:otherwise>
    </c:choose>
</spring:bind>

Binding a multiple checkboxes to an array property of a form bean

The form contains a List named types. These are pojos that have a checked attribute. Spring sets this property after the form is submitted. In the form processing code these checked properties can be read and acted on.

<c:forEach items="${form.types}" var="type" varStatus="loopStatus">
    <spring:bind path="types[${loopStatus.index - 1}].checked">
                ${status.errorCode}
                <input type="hidden" name="_${status.expression}"/>
        <c:choose>
            <c:when test="${status.value}">
                <input type="checkbox" name="${status.expression}" 
                    value="true" checked="checked"/>
            </c:when>
            <c:otherwise>
                <input type="checkbox" name="${status.expression}"
                    value="true"/>
            </c:otherwise>
        </c:choose>
    </spring:bind>
</c:forEach>