Java Tutorial/JSTL/Choose
Содержание
Choose When and Otherwise
<%@ taglib uri="http://java.sun.ru/jstl/core" prefix="c" %>
<%@ taglib uri="http://java.sun.ru/jstl/core-rt" prefix="c-rt" %>
<html>
<head>
<title>Count to 10 Example(tracking even and odd)</title>
</head>
<body>
<table border="0">
<c:forEach var="i" begin="1" end="10" varStatus="status">
<jsp:useBean id="status" type="javax.servlet.jsp.jstl.core.LoopTagStatus" />
<c-rt:choose>
<c-rt:when test="<%=status.getCount()%2==0%>">
<c:set var="color" value="#eeeeee" />
</c-rt:when>
<c-rt:otherwise>
<c:set var="color" value="#dddddd" />
</c-rt:otherwise>
</c-rt:choose>
<tr>
<td width="200" bgcolor="<c:out value="${color}"/>">
<c:out value="${i}" />
</td>
</tr>
</c:forEach>
</table>
</body>
</html>
Choose When Statement
<%@ taglib uri="http://java.sun.ru/jstl/core" prefix="c" %>
<html>
<head>
<title>Using Choose,Otherwise and When</title>
</head>
<body>
<c:if test="${pageContext.request.method=="POST"}">You entered:
<c:choose>
<c:when test="${param.enter=="1"}">One
<br />
</c:when>
<c:when test="${param.enter=="2"}">Two
<br />
</c:when>
<c:when test="${param.enter=="3"}">Three
<br />
</c:when>
<c:when test="${param.enter=="4"}">Four
<br />
</c:when>
<c:when test="${param.enter=="5"}">Five
<br />
</c:when>
<c:otherwise>
<c:out value="${param.enter}" />
<br />
</c:otherwise>
</c:choose>
</c:if>
<form method="post">Enter a number between 1 and 5:
<input type="text" name="enter" />
<input type="submit" value="Accept" />
<br />
</form>
</body>
</html>
Choose XML Data with Comparision
JSTL code
<%@ taglib uri="http://java.sun.ru/jstl/core" prefix="c" %><%@ taglib uri="http://java.sun.ru/jstl/xml" prefix="x" %>
<html>
<head>
<title>For Each Examples</title>
</head>
<body>
<c:import var="students" url="students.xml" />
<x:parse var="doc" xml="${students}" />
<table border="1">
<tr>
<TH>First</th>
<TH>Last</th>
<TH>Points</th>
<TH>Letter</th>
<TH>Note</th>
</tr>
<x:forEach var="student" select="$doc/students/student">
<tr>
<td>
<x:out select="name/first" />
</td>
<td>
<x:out select="name/last" />
</td>
<td>
<x:out select="grade/points" />
</td>
<td>
<x:out select="grade/letter" />
</td>
<td>
<x:choose>
<x:when select="grade/points>90">You did
great!</x:when>
<x:when select="grade/points>80">You did
good!</x:when>
<x:when select="grade/points>75">You did
ok.</x:when>
<x:when select="grade/points>70">Well, you
passed.</x:when>
<x:otherwise>You failed</x:otherwise>
</x:choose>
</td>
</tr>
</x:forEach>
</table>
</body>
</html>
Combine If Chooser to Report Exception
<%@ taglib uri="http://java.sun.ru/jstl/core" prefix="c" %>
<%
int i= (int) (Math.random() * 10);
pageContext.setAttribute("signalStrength", new Integer(i), PageContext.PAGE_SCOPE);
%>
<html>
<head>
<title>The c:catch action</title>
</head>
<body>
<c:if test="${pageScope.signalStrength < 5}">
<c:set var="signalFailure" value="true" scope="page" />
</c:if>
<c:choose>
<c:when test="${pageScope.signalFailure == true}">
<h3>Exception!</h3>
Refresh the page in your web browser to try again.
</c:when>
<c:otherwise>
<h3>No Exception.</h3>
Refresh the page in your web browser to make another call.
</c:otherwise>
</c:choose>
</body>
</html>
Tag Examples - choose
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-->
<html>
<head>
<title>Tag Examples - choose</title>
</head>
<body>
<h1>Tag Plugin Examples - <c:choose></h1>
<font color="#000000"/>
</br>
<%@ taglib uri="http://java.sun.ru/jstl/core" prefix="c" %>
<c:forEach var="index" begin="0" end="4">
#<c:out value="${index}"/> :
<c:choose>
<c:when test="${index == 1}">
One!</br>
</c:when>
<c:when test="${index == 4}">
Four!</br>
</c:when>
<c:when test="${index == 3}">
Three!</br>
</c:when>
<c:otherwise>
Huh?</br>
</c:otherwise>
</c:choose>
</c:forEach>
</body>
</html>
