Escape single quotes in a string [duplicate]

Question

JSP:

<% final String data = "some test with ' single quotes"; %>
<script>
    var str = '<%= data %>';
<script>

The result is (JavaScript):

var str = 'some test with ' single quotes';

Uncaught SyntaxError: Unexpected identifier

How do I replace this single quote with \' to avoid a JavaScript error?

Answer 1

Use escapeEcmaScript method from Apache Commons Lang package:

Escapes any values it finds into their EcmaScript String form. Deals correctly with quotes and control-chars (tab, backslash, cr, ff, etc.). So a tab becomes the characters '\\' and 't'.

The only difference between Java strings and EcmaScript strings is that in EcmaScript, a single quote and forward-slash (/) are escaped.

Example:

input string: He didn't say, "Stop!"

output string: He didn\'t say, \"Stop!\"

Answer 2

Remember you also need to encode the double quotes, new lines, tabs and many other things. One way to do it is using org.apache.commons.lang.StringEscapeUtils

public class JavaScriptEscapeTest {

    public static void main(String[] args) throws Exception {

        String str = FileUtils.readFileToString(new File("input.txt"));
        String results = StringEscapeUtils.escapeEcmaScript(str);
        System.out.println(results);

    }

}

input.txt

Here is some "Text" that I'd like to be "escaped" for JavaScript. I'll try a couple special characters here: \ "

output

Here is some \"Text\" that\r\nI\'d like to be \"escaped\" for JavaScript.\r\nI\'ll try a couple special characters here: \ \"