Concat two String in JSF EL expression [duplicate]

问题

This question already has an answer here:

How to concatenate Strings in EL expression? (1 answer)

Closed 4 years ago.

I have the following el expression:

<af:outputText value="#{viewArticle.publish ? ('Publish on ' + viewArticle.publishDate + ' by ' + viewArticle.publishFirstName + ' ' + viewArticle.publishLastName) : 'Draft version'}"/>

But I am getting

java.lang.NumberFormatException: For input string: "Publish on "

How can I join the string?

回答1:

You can use the String.concat function:

<af:outputText value="#{viewArticle.publish ? 'Publish on '.concat(viewArticle.publishDate).concat(' by ').concat(viewArticle.publishFirstName).concat(' ').concat(viewArticle.publishLastName) : 'Draft version'}"/>

回答2:

You should write

value  = "#{someBean.aProperty}  something you want in between #{someBean.anotherProperty}"

回答3:

You have to write a custom EL function. This example will help you :)

来源：https://stackoverflow.com/questions/17102614/concat-two-string-in-jsf-el-expression