The use of C tag in JSP personal summary __js

The C tag we use in web development is the core library in Jstl, providing common support for everyday tasks

<C:SET>: Setting variable values and Object properties

<c:set value= "value var=" variable name "scope=" variable's scope "target=" Object name property= "object property name" ></c:set>

<C:OUT>: Display variable contents in page

No label body:

Has the label body:

<c:out value= "value" escapexml= "{true|false}" default= "Default Value" >  label Body </c:out>

Conditional label:<c:if> <c:choose> <c:when> <c:otherwise>

No label body:

<c:if test= "test condition" var= "variable name" [scope= scope]/>      

Has the label body:

<c:if test= "test condition" var= "variable name" [scope= scope]>       

<c:when> <c:otherwise> cannot be used alone and can only be used as a child label for <c:choose>.

These three tags combine to implement the functionality of the switch statements in Java. The syntax is as follows:

    <c:choose> 

        <c:when test= "${user.class== ' guest '}" >
             tag body 1  

        </c:when> 

        <c:when test= "${user.class== ' VIP '}" >

            label body 2 

       </c:when>    

       <c:otherwise> 

            label Body 3 

       </c:o Therwise>    
    </c:choose>  

Iteration Label:

<c:forEach> <c:forTokens> to traverse an object collection

<c:foreach var= "variable name" items= "collection" varstatus= "Traversal state name"   begin= "Begin" end= "End" step= "Step" > 

       label body

</c:forEach>

<c:fortokens>: Used to traverse a string, and each traversal result returns a word in the string.

<c:fortokens items= "string" delims= "delimiter" var= "variable name" varstatus= "Traversal state name" begin= "Begin" end= "End" step= "Sep" > 

       tag Body

</c:forTokens>

<c:url>: Used to encode URL addresses.

Has the label body:

<c:url value= "url" context= "path" var= "variable name" scope= "Scope" >  

The following code:

  <c:url value= "http://localhost:8080/el/index.jsp" var= "Newurl" >

       <c:param "name" name= "Zero"/ > 

        <c:param name= "age" value= "/> 

 </c:url> 

<a href=" ${newurl} "> Dot me </a>

Generated url:http://localhost:8080/el/index.jsp?name=zero&age=28

No label body: used primarily for editing context URLs.

<c:url value= "url" context= "path" var= "variable name" scope= "Scope"/>      

The following code:

   <c:url value= "/logon.jsp" > Login </c:url>  

If the current path is El, the output is:/el/logon.jsp

。。。。。。