Is it possible to access a String type variable defined in jsp from a javascript on the same page?
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=windows-1255">
<title>Insert title here</title>
<script type="text/javascript">
foo();
function foo()
{
var value = "<%=myVar%>";
alert(value);
}
</script>
</head>
<body>
<%
String myVar="blabla";
%>
</body>
</html>
In eclipse I am getting an error
myVar cannot be resolved to a variable
This won't work since you're trying to use an undefined variable. The code is generated like this:
... = myVar;
//...
String myVar = "blabla";
Doesn't make sense, right? So, in order to make this work you should declare the variable before using it (as always):
<%
String myVar="blabla";
%>
<script type="text/javascript">
foo();
function foo() {
var value = "<%=myVar%>";
alert(value);
}
</script>
Still, usage of scriptlets is extremely discouraged. Assuming you're using JSTL and Expression Language (EL), this can be rewritten to:
<c:set name="myVar" value="blabla" />
<script type="text/javascript">
foo();
function foo() {
var value = "${myVar}";
alert(value);
}
</script>
If your variable has characters like " inside, then this approach will faile. You can escape the result by using <c:out> from JSTL:
var value = "<c:out value='${myVar}' />";
More info:
<%and<%=blocks are evaluated in the order in which they're found on the page. You need to put the one that declaresmyVarbefore the one that uses it.