（19）Struts2_表单标签

        input: <input type=“submim” …/>
        button: <input type=“button” …/>
        image: <input type=“image” />

    <!-- form-tag.jsp -->
    <s:form action="save">
        <s:hidden name="userId"></s:hidden>
        <s:textfield name="userName" label="UserName"></s:textfield>
        <s:password name="passWord" label="Password"></s:password>
        <s:textarea name="desc" label="Desc"></s:textarea>
        <s:submit></s:submit>
        <s:checkbox name="merried" label="是否已婚" ></s:checkbox>
    </s:form>

    //UserAction.java
    private String userId;
    private String userName;
    private String passWord;
    private String desc;
    private boolean merried;

    public boolean isMerried() {
        return merried;
    }

    public void setMerried(boolean merried) {
        this.merried = merried;
    }

    public String getUserId() {
        return userId;
    }

    public void setUserId(String userId) {
        this.userId = userId;
    }

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    public String getPassWord() {
        return passWord;
    }

    public void setPassWord(String passWord) {
        this.passWord = passWord;
    }

    public String getDesc() {
        return desc;
    }

    public void setDesc(String desc) {
        this.desc = desc;
    }

        <!-- 表单提交后，重新跳转到form-tag.jsp -->
        <action name="save" class="com.qbz.struts2_02.UserAction" method="save">
            <result name="input">/form-tag.jsp</result>
        </action>

<s:checkbox name="merried" label="是否已婚" ></s:checkbox>

<input type="checkbox" name="merried" value="true" checked="checked" id="save_merried"/>
<input type="hidden" id="__checkbox_save_merried" name="__checkbox_merried" value="true" /> 
<label for="save_merried" class="checkboxLabel">是否已婚</label> </td>

<s:form action="save">
    <s:checkboxlist name="citys" list="#session.list" listKey="cityId" listValue="cityName"></s:checkboxlist>
    <s:submit></s:submit>
</s:form>

    private List<String> citys;

    public List<String> getCitys() {
        return citys;
    }

    public void setCitys(List<String> citys) {
        this.citys = citys;
    }


    public String save() {
        System.out.println(this);
        List<City> cities = new ArrayList();

        cities.add(new City("1001", "北京"));
        cities.add(new City("2001", "上海"));
        cities.add(new City("3001", "广州"));
        cities.add(new City("3002", "深圳"));
        cities.add(new City("4001", "杭州"));
        ActionContext.getContext().getSession().put("list", cities);
        return "input";
    }

        <s:select name="city" list="#session.list" listKey="cityId" listValue="cityName">
            <s:optgroup label="Test" list="#session.list" listKey="cityId" listValue="cityName"></s:optgroup>
        </s:select>

private String city;

    public String getCity() {
        return city;
    }

    public void setCity(String city) {
        this.city = city;
    }

<s:radio list="#session.list" listKey="cityId" listValue="cityName" name="rcity"></s:radio>

private String rcity;

    public String getRcity() {
        return rcity;
    }

    public void setRcity(String rcity) {
        this.rcity = rcity;
    }