Tag:El expression

  • JSP does not support El expression, the solution is

    Time:2021-7-20

    If you have the following, it means servlet 2.3 / JSP 1.2.<!–CTYPE web-app PUBLIC </sp–> “-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN” “http://java.sun.com/dtd/web-app_2_3.dtd”> By default, servlet 2.3/jsp 1.2 does not support El expressions, while servlet 2.4/jsp 2.0 does.If the following settings of web.xml do not support El expressions:<web-app version=”2.5″ xmlns=”http://java.sun.com/xml/ns/javaee” xmlns:xsi=”http://www.w3.org/2001/XMLSchema-instance” xsi:schemaLocation=”http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd”> resolvent:1. Modify the […]

  • Detailed explanation of JSP El expression

    Time:2021-7-9

    catalogue 1、 Introduction to El expression Grammatical format 2、 El get data (get attributes from four domains) 3、 Built in objects in El 1. Domain attribute related (4) 2. Other important built-in objects (4) 1、pageContext 2. Param (get the specified parameters in the request) 3、paramValues 4、initParam 4、 El accessing bean properties 1. What is java […]

  • JSP El expression in detail

    Time:2021-6-8

    1、 JSP El language definition         E L(Expression Language)   Purpose: to makeJSP is easier to write.        The inspiration of expression language comes from ECMAScript and XPath expression language, which provides a way to simplify expressions in JSP. It is a simple language based on the available namespace (pagecontext attribute), nested attributes and accessors […]

  • The solution of JSP can’t parse El expression

    Time:2021-5-13

    The reason is: by default, servlet 2.4 / JSP 2.0 supports El expressions. There are two solutions 1. Modify the beginning definition of web.xml. Copy codeThe code is as follows: <web-app version=”2.4″ xmlns=”http://java.sun.com/xml/ns/j2ee” xmlns:xsi=”http://www.w3.org/2001/XMLSchema-instance” xsi:schemaLocation=”http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd”> This configuration represents servlet 2.4 / JSP 2.0. 2. Add a code at the beginning of the page where […]

  • The application of El expression in JSP

    Time:2020-2-25

    El operator: <%@page language=”java” contentType=”text/html;charset=gb2312″%> <%@page import=”java.sql.*” %> <!DOCTYPE html> <html> <head> < title > El arithmetic operator < / Title > </head> <body> <table border=1> <tr> <td>Arithmetic operator</td> <td>Results</td> </tr> <tr> <td>Addition operator \ ${1 + 1}</td> <td>Result ${1 + 1}</td> </tr> <tr> <td>Subtraction operators \ ${1 – 1}</td> <td>Result ${1-1}</td> </tr> <tr> <td>Multiplication […]

  • Introduction to El expression (recommended)

    Time:2020-2-7

    In order to makeJSPIt’s easier to write.The inspiration of expression language comes from ECMAScript and XPath Expression language, which provides JSP To simplify the expression. JSP El language definition E L(Expression Language)Purpose: in order toJSPIt’s easier to write. The inspiration of expression language comes from ECMAScript and XPath Expression language, which provides JSP To simplify […]

  • The solution to the problem that El expression in JSP page is treated as string and does not display value

    Time:2020-1-11

    When I practiced, I encountered the phenomenon that El expressions were treated as strings without proper parsing. Java ee5 used in the project at that time, web.xml <web-app version=”2.5″ xmlns=”http://java.sun.com/xml/ns/javaee” xmlns:xsi=”http://www.w3.org/2001/XMLSchema-instance” xsi:schemaLocation=”http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd” > El expression is not parsed. It is treated as a string. Later, we changed web.xml to <web-app version=”2.4″ xmlns=”http://java.sun.com/xml/ns/j2ee” xmlns:xsi=”http://www.w3.org/2001/XMLSchema-instance” xsi:schemaLocation=”http://java.sun.com/xml/ns/j2ee […]

  • Detailed explanation of the usage of El expression in JSP (required article)

    Time:2019-10-27

    El full name is expression language El syntax is very simple, its biggest feature is very convenient to use. Next, the main syntax structure of El is introduced: ${sessionScope.user.sex} All EL starts with ${and ends with}. The above El example means: from the scope of the session, get Gender of the user. If you write […]

  • Talking about the Value Selection Process of JSP EL Expressions, the Difference between Page and Page Context

    Time:2019-10-10

    1. EL expression parsing process In JSP, we often write the words ${obj. name}, but have you ever thought about the process of its value taking and where to get the attribute value? The phrase ${obj} corresponds to request. getAttribute (“obj”), which is not strictly rigorous, and the request range is page, request, session, application […]

  • Talking about EL Expressions of the Way to Obtain Parameters in Spring MVC JSP Front Desk

    Time:2019-3-12

    JAVA: request.setAttribute(“msg”, “1234”); session.setAttribute(“msg2”, “1234”); JSP: ${requestScope.msg} ${sessionScope.msg2} JAVA: Parameters added in Model AndView Model Map Model JSP: Use ${parameter name} directly JAVA: The information in the front-end form, or directly after the url? Name = value & Name2 = Value2 passed to the background JSP: ${param. parameter name} corresponds to JAVA request. getParameter (“parameter […]