Using multiple boolean conditions in EL expression

问题

I would like to know how can I combine multiple boolean coniditions in EL. I have following example and it is not working.

<x:someComponent rendered="#{bean.condition1} or #{bean.condition2}">

How can I use "OR" and "AND" logical operators in EL?

回答1:

The operator has to go inside the EL expression, not outside. You should see the #{...} as one big scope wherein various variables/conditions interact with each other.

<x:someComponent rendered="#{bean.condition1 or bean.condition2}">

See also:

• Our EL wiki page
• Conditionally displaying JSF components
• How to conditionally render plain HTML elements like <div>s?

回答2:

The operator OR in an expression EL is ||.

Try this:

<ice:panelCollapsible  rendered ="#{mySessionBean.buttonVisibilities['myButton1'] || mySessionBean.buttonVisibilities['myButton2']}">

See this tutorial http://docs.oracle.com/javaee/1.4/tutorial/doc/JSPIntro7.html

Regards

来源：https://stackoverflow.com/questions/11064412/using-multiple-boolean-conditions-in-el-expression