Concat在JSF EL表达式中的两个字符串

Question

我有以下表达式：

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

但我得到了

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

我如何加入字符串？

Answer 1

您可以使用 String.concat 功能：

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

Answer 2

你应该写

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

Answer 3

您必须编写自定义EL功能。 This example会帮助你:)