JSP standard library label ——— c tag

One, c label
A "<c:out value=" ... "default=" ... "escapexml=" true ">
EscapeXML: Escapes the special symbol in value. If not specified as false, the default value is true.
Value: Output to values in the browser
Default value when the Default:value value is not found
Code

  <c:out value= "Hello word! "/> <% Pagecontext.setattribute (" username "," Jack "); %> <br/> <c:out value=" ${username} "/&G T <BR/> <c:out value=" ${fdusername} "default  = "Unknown"/> <br/> link:  <c:out value= "< ; a href= ' # ' > Download </a> "escapexml=" false "/> <br/> link:  <c            : Out value= "<a href= ' # > Download </a>" escapexml= "true"/> <br/> Link:  <c:out value= "<a href= ' # ' > Downloads </a>"/> <br/>  

　　　　

Two "<c:set var/value/scope/target/property>
var: there are 20% meanings. The variable name and the name of the domain object to be stored.
Target and property are for JavaBean.

Code

<c:set var= "name" value= "Jack" scope= "page"/> <c:out value= "${name}"/> <br/> <j Sp:usebean id= "User"class= "Com.suse.domain.User" scope= "page"/> <c:set target= "${user}" property= "UserName" value= "Jack"/> <c:out value= "${user.username}"/> <br/> <%Map<string, integer> map =NewHashmap<string, integer>(); Pagecontext.setattribute ("Map", map); %> <c:set target= "${map}" property= "Key" value= "Jack"/> <c:set target= "${map}" property = "value" value= "7000"/> <c:out value= "${map.key}"/> <br/> <c:out val Ue= "${map.value}"/>

Three "<c:remove/>
<c:remove var= "VarName" [scope= "{page|request|session|application}"]>
Code

            <c:set var= "name" value= "Jack" scope= "page"/>            default= "Unknown"/>            <c:remove var= "name" Scope= "page"/>            default= "Unknown"/>

      Four "<c:catch var=" ... "
        </c: Cath>
         Code:

            <c:catch var= "message" >                <%                    int a = 10/0;                 %>            </c:catch>            default= "no exception!" "/>

      Five "<c:if var/test/scope;
             var: Saves the result of the Test property. True or False
            scope: Saves the result of the test property to which domain object.

            <c:if test= "${25>16}" var= "flag" scope= "request" >                25>16            </c:if>            <jsp:forward page= "value.jsp"/>

　　　　
Six "<c:choose>
<c:when test= "..." >
.....
</c:when>
<c:otherwise>
.....
</c:otherwise>
</c:choose>

**${param.age} Gets the value of the address bar parameter age

Code:

            <c:choose>                <c:when test= "${param.age >" >                     you're grown up                 </c:when>                <c:o Therwise>                     You're still                underage </c:otherwise>            </c:choose>

seven "<c:foreach var/items/varstatus/begin/end/step>. </c:forEach>

var: Saves the currently iterated element to the page property name in this domain object
Items: The collection object to iterate on
varstatus: is a page domain object. Holds the information for this iteration.
Property: First: Whether it is a (true or false) Index: current subscript
Count : Count end: Is the last (true or false)

            <%  List　　new arraylist<string>();       List.add (　　"Jack"); 　　           List.add ("Merry"); 　　           List.add ("Berry");          List.add ("Xixi");          List.add (　　"Sisi");           Request.setattribute ("list", list);             %>            <c:foreach var= "item" items= "${list}" varstatus= "status" >                -${item}-${ Status.first}-${status.last}-${status.count} <br/>            </c:forEach>

JSP standard library label ——— c tag