How to put “new line” in JSP's Expression Lang

问题:

What would be right EL expression in JSP to have a new line or HTML's <br/>? Here's my code that doesn't work and render with '\n' in text.

<af:outputText value="#{msg.TCW_SELECT_PART_ANALYSIS}\n#{msg.TCW_SELECT_PART_ANALYSIS2}"/>

回答1:

Since you want to output <br />, just do:

<af:outputText value="#{msg.TCW_SELECT_PART_ANALYSIS}<br />#{msg.TCW_SELECT_PART_ANALYSIS2}" escape="false" />

The attribute escape="false" is there to avoid the <br /> being HTML-escaped.

You can even display the two messages in separate tags and put the <br /> in plain text between them.

<af:outputText value="#{msg.TCW_SELECT_PART_ANALYSIS}" />
<br />
<af:outputText value="#{msg.TCW_SELECT_PART_ANALYSIS2}" />

If you're still on JSF 1.1 or older, then you need to wrap plain HTML in <f:verbatim> like:

<f:verbatim><br /></f:verbatim>

回答2:

If you want a new line in the browser then you need to put "<br/>" in the text. The browser will then interpret it correctly. It does not understand \n.

回答3:

How about:

<af:outputText value="#{msg.TCW_SELECT_PART_ANALYSIS}"/>
<af:outputText value="#{msg.TCW_SELECT_PART_ANALYSIS2}"/>

(i.e. split the value and put the character you want between the two)?

回答4:

Write a custom function that calls this piece of code:

import java.util.StringTokenizer;

public final class CRLFToHTML {

    public String process(final String text) {

        if (text == null) {
            return null;
        }

        StringBuilder html = new StringBuilder();

        StringTokenizer st = new StringTokenizer(text, "\r\n", true);

        while (st.hasMoreTokens()) {
            String token = st.nextToken();

            if (token.equals("\n")) {
                html.append("<br/>");
            } else if (token.equals("\r")) {    
                // Do nothing    
            } else {    
                html.append(token);    
            }
        }

        return html.toString();

    }

}