Question

I have a JavaScript function which does not give the result I want.

Here is the code (it is a part of a JavaScript function):

<%
    String myStringVariable = "no";
%>

alert("yes");                  // This alert gets shown.
alert(<%=myStringVariable%>);  // But this alert doesn't get shown.

I do not understand why the second alert does not work. Can someone identify the reason?

Answer 1

Like as in Java, in JavaScript should strings be quoted.

alert("<%=myStringVariable%>"); 

You need to realize that this code doesn’t run in sync. It’s Java/JSP which runs first, generates a bunch of HTML/CSS/JS and sends it to the browser. Then it’s HTML/CSS/JS turn to run. If you do a rightclick, View Source in browser, you’ll see that Java/JSP has already done its job and there should be no single line of it.

See also:

• Our JSP wiki page – Contains a chapter about JavaScript