jsp四种属性范围（JSP four range of attributes）.docVIP

jsp四种属性范围（JSP four range of attributes） 3.1.1, operation method Use the following method in the JAVA WEB operation attributes: Set properties: public (String void setAttribute name, Object attribute) Object getAttribute - has attributes: public (String name) Object removeAttribute - deleted attribute: public (String name) There are four methods to support the above three objects in JSP: Page (pageContext) Request Session Application 3.1.2, page attribute range The property can be set in a JSP page in a page, jump to other pages of this property disappear. PageScopeDemo01.jsp: %@page contentType= text/html; charset=GBK% %@page import= java.util.*% Set / / two attributes PageContext.setAttribute (uname, HELLO); PageContext.setAttribute (udate), new (Date); Get / attribute String = name (String) pageContext.getAttribute (uname); Date = date (Date) pageContext.getAttribute (udate); % h1name / %=name%/h1 h1date / %=date%/h1 The current page can obtain the attribute set, to modify the page below, to complete a jump. PageScopeDemo02.jsp: %@page contentType= text/html; charset=GBK% %@page import= java.util.*% Set / / two attributes PageContext.setAttribute (uname, HELLO); PageContext.setAttribute (udate), new (Date); % jsp:forward page= PageScopeDemo03.jsp / PageScopeDemo03.jsp: %@page contentType= text/html; charset=GBK% %@page import= java.util.*% Get / attribute String = name (String) pageContext.getAttribute (uname); Date = date (Date) pageContext.getAttribute (udate); % h1name / %=name%/h1 h1date / %=date%/h1 That property is set on a page, only in this page. If we hope to get the jump page, you can expand the range of up to request. 3.1.3, request attribute range Request can be stored in a server attribute jump range. RequestScopeDemo01.jsp: %@page contentType= text/html; charset=GBK% %@page import= java.util.*% Set / / two attributes Request.setAttribute (uname, HELLO); Request.setAttribute (udate), new (Date); % jsp:forward page= RequestScopeDemo02.