JSF参数传递

参考：JSF参数传递方式

1 f:param标签

1.1 前后端的参数传递

1.1.1 请求页面

<h:form>
    <h:commandLink value="Test2" action="#{paramBean.test}">
        <f:param name="name" value="zhang"></f:param>
        <f:param name="id" value="123456"></f:param>
    </h:commandLink>
</h:form>

注意:这里只能使用h:commandLink标签，而不能使用h:commandButton标签!

1.1.2 后台取参数

1 通过Request对象取值

HttpServletRequest request = (HttpServletRequest)FacesContext.getCurrentInstance().getExternalContext().getRequest();
request.getParameter("name");

2 通过RequestParameterMap取值

Map varMap = FacesContext.getCurrentInstance().getExternalContext().getRequestParameterMap();
varMap.get("id");

3 通过配置文件进行Bean的属性值注入，在Bean的方法中直接使用属性

<managed-bean>
    <managed-bean-name>paramBean</managed-bean-name>
    <managed-bean-class>com.spg.bean.ParamBean</managed-bean-class>
    <managed-bean-scope>request</managed-bean-scope>
    <managed-property>
        <property-name>id</property-name>
        <property-class>java.lang.String</property-class>
        <value>#{param.id} </value>
    </managed-property>
</managed-bean>

1.2 页面到页面的参数传递

1.2.1 请求页面

• 第1种

<h:outputLink value="param2.jsf">
    <h:outputText value="Test4"></h:outputText>
    <f:param name="name" value="chen"></f:param>
    <f:param name="id" value="123456"></f:param>
</h:outputLink>

• 第2种

<h:outputLink value="param2.jsf?name=chen&id=123456">
    <h:outputText value="Test4"></h:outputText>
</h:outputLink>

注意：以上两种方法，不能同时使用!

1.2.2 页面中取参数

1 使用JSF的值表达式

<h:outputText value="#{param.name}"></h:outputText>
<h:outputText value="#{param.id}"></h:outputText>

2 使用JSP的表达式

<%=request.getParameter("name")%>
<%=request.getParameter("id")%>

2 Backing Bean 与 h:inputHidden标签

Backing Bean

import javax.faces.component.UIInput;
import javax.faces.component.UIOutput;

public class BackingBean {

    private UIOutput idComponent;

    public UIOutput getIdComponent() {
        return idComponent;
    }

    public void setIdComponent(UIOutput idComponent) {
        this.idComponent = idComponent;
    }
}

2.1 前后端的参数传递

2.1.1 请求页面

<h:form>
    <h:inputHidden value="123456" binding="#{backingBean.idComponent}"></h:inputHidden>
    <h:commandButton value="登录" action="#{paramBean.login}"></h:commandButton>
</h:form>

2.1.2 后台取参数

FacesContext context = FacesContext.getCurrentInstance();
BackingBean backBean =(BackingBean)context.getApplication().getVariableResolver().resolveVariable(context,"backingBean");//该方法已经过时
BackingBean bean =(BackingBean)context.getApplication().getELResolver().getValue(context.getELContext(), null, "backingBean");
backBean.getIdComponent().getValue();
bean.getIdComponent().getValue();

FacesContext context = FacesContext.getCurrentInstance();

2.2 页面到页面的参数传递

2.2.1 请求页面

<h:form>
    <h:inputHidden value="123456" binding="#{backingBean.idComponent}"></h:inputHidden>
    <h:commandButton value="Test5" action="param"></h:commandButton>
    <h:commandLink value="Test6" action="param"></h:commandLink>
</h:form>

注意：h:outputLink 标签不能使用该方式传递参数！

2.2.2 页面中取参数

<h:outputText value="#{backingBean.idComponent.value}"></h:outputText>

3 通过session(application)对象传递

3.1 前后端的参数传递

3.1.1 请求页面

<h:form>
    <%session.setAttribute("name","hujilie"); %>
    <%application.setAttribute("id","123456"); %>
    <h:commandButton value="Test8" action="#{paramBean.test2}"></h:commandButton>
    <h:commandLink value="Test8" action="#{paramBean.test2}"></h:commandLink>
</h:form>

3.1.2 后台取参数

FacesContext context = FacesContext.getCurrentInstance();
Map sessionMap =context.getExternalContext().getSessionMap();
Map applicationMap = context.getExternalContext().getApplicationMap();
HttpSession session =(HttpSession) context.getExternalContext().getSession(true);
ServletContext application = (ServletContext)context.getExternalContext().getContext();
sessionMap.get("name");
applicationMap.get("id");
session.getAttribute("name");
application.getAttribute("id");

3.2 页面到页面的参数传递

3.2.1 请求页面

<h:form>
    <%session.setAttribute("name","hujilie"); %>
    <%application.setAttribute("id","123456"); %>
    <h:outputLink value="param2.jsf">Test10</h:outputLink>
</h:form>

3.2.2 页面中取参数

<h:outputText value="#{sessionScope.name}"></h:outputText><br>
<h:outputText value="#{applicationScope.id}"></h:outputText>

4 f:attribute标签传递

4.1 前后端的参数传递

4.1.1 请求页面

<h:form>
    <h:commandButton action="#{paramBean.test3}" value="Test11" actionListener="#{paramBean.changeName}">
        <f:attribute name="name" value="hujilie"/>
    </h:commandButton>
    <h:commandLink action="#{paramBean.test3}" value="Test12" actionListener="#{paramBean.changeName}">
        <f:attribute name="name" value="hujilie"/>
    </h:commandLink>
</h:form>

4.1.2 后台取参数

public void changeName(ActionEvent e) {
    UIComponent component = e.getComponent();
    Map<String, Object> map = component.getAttributes();
    setName((String)map.get("name"));
}

5 f:setPropertyActionListener 标签传递

5.1 前后端的参数传递

5.1.1 请求页面

<h:form>
    <h:commandButton action="#{paramBean.test3}" value="Test14">
        <f:setPropertyActionListener value="hujilie" target="#{paramBean.name}"/>
    </h:commandButton>
    <h:commandLink action="#{paramBean.test3}" value="Test15">
        <f:setPropertyActionListener value="hujilie" target="#{paramBean.name}"/>
    </h:commandLink>
</h:form>

5.1.2 后台取参数

直接使用属性的值。