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@Variable Directive

Sunder Ganapathy
Ranch Hand

Joined: Apr 01, 2003
Posts: 120
I have tried to see the working of Variable directive in Tag Files.

The expression ${x} does not get evaluated. Why?

Tag File : ( Header.Tag )


<%@ variable name-given="x" scope="AT_END" %>
<c:set var="x" value="5" />

<%@ attribute name="subTitle" required="true" rtexprvalue="true" %>

<img src="GTITLE.gif"> <br>
<h1>Hi, </h1>
<em><strong>${subTitle}</strong></em> <br>

JSP File : ( Header.JSP)

<%@ taglib prefix="myTags" tagdir="/WEB-INF/tags" %>

<html>
<head>
<title>Header Tags Example</title>
</head>

<body bgcolor="#660099">
<h3>Simple Header Tag</h3>

${x}

<myTags:Header subTitle="We take the Sting out of SOAP" >
${x}
</myTags:Header>

${x}
<c ut value="${x}" />
Welcome to our site.

</body>
</html>

Actually in the source I could see the value of x being set to 5.
But, the expression of ${x} is not evaluated.
I tried all three properties, AT_END, AT_BEGIN & NESTED.
Shivani Chandna
Ranch Hand

Joined: Sep 18, 2004
Posts: 380
Hello Sunder,

When you specify :



Means x is a variable whose value will be going out from the tag to the calling jsp file. Its an OUT (or like a return type variable)....

In the Tag file you can modify the value.


Doing so would allow the ~~return value to be synchronized depending on the scope specified.

Also note, that the OUT variables do not get initialized with the values specified in the calling jsp files - but are only capable of setting values in these variable - that are to be returned.


Note: I do hope that you are importing the Jstl core library in the tag file so that c:set works correctly?.

Regards,
Shivani.
[ July 25, 2006: Message edited by: Shivani Chandna ]

/** Code speaks louder than words */
 
I agree. Here's the link: http://aspose.com/file-tools
 
subject: @Variable Directive