The El language in JSP

1,el (expression Language) is an expression language inspired by JavaScript,

2,el expressions contain literals, operators, variables, function calls;

3,el The syntax format of the access variable: ${username}, which represents a variable named username in a range;

Because there is no indication of the scope of the username, so will be in the page, request, session, application within the scope of the search, if found username, the direct callback, no longer continue to find, otherwise return null;

4,${username}//Direct output of username in curly braces;

\${username}//Output ${username}

The El language in JSP