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- ASP
- 从文本文件中读取信息并存储入数据库
- 文本搜索
- FileSystemObject处理文件
- 设计 FileSystemObject
- 处理驱动器和文件夹
- 用ASP做一个TOP COOL的站内搜索
- 怎样读取一个文本文件的内容?
- 在线用表单建立文件夹
- filesystemobject组件的用法示例
- ASP中文本文件与数据库文件的数据交换(FSO)
- 读取目录下的所有文件(包括子目录下的所有文件)
- ASP中FSO的神奇功能 - FSO不能做到的
- ASP中FSO的神奇功能 - 用FSO进行内容管理
- ASP中FSO的神奇功能 - 使用FSO进行搜索
- ASP中FSO的神奇功能 - 权限许可
- ASP中FSO的神奇功能 - 文件读取
- ASP中FSO的神奇功能 - 写文件
- ASP中FSO的神奇功能 - 简介
- 读取目录下的文件得到一个数组
- 奇妙的文件系统对象组件
ASP 中的 javascript asp教程第十一课--Application 对象
出处:互联网 整理: 软晨网（RuanChen.com） 发布: 2009-09-13 浏览: 58 ::
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Overview:
The Application Object represents a collection of ASP pages. The Application object has zero (0) properties, two (2) collections, two (2) methods, and two (2) events.
Get Started:
Below are a couple scripts for lesson11.
<%@LANGUAGE="JavaScript"%> <% //No ASP Here, just a regular HTML Page %> <HTML> <FORM ACTION="script11a.asp" METHOD="Post"> <STRONG>Would you like to chose the official Application color?</STRONG><BR> <SELECT NAME="OfficialColor"> <OPTION>red</OPTION> <OPTION>white</OPTION> <OPTION>blue</OPTION> </SELECT><BR> <INPUT TYPE="Submit" VALUE="Yes, click here"> </FORM> No, <A HREF="script11a.asp">click here</A>. </HTML>
Click Here to run script11.asp in a new window. Below is script11a.asp.
<%@LANGUAGE="JavaScript"%>
<HTML>
<%
Application.Lock()
var OfficialColor = new String( Request.Form("OfficialColor") )
if (OfficialColor=="red") { Application("OfficialColor") = "red" }
if (OfficialColor=="white") { Application("OfficialColor") = "white" }
if (OfficialColor=="blue") { Application("OfficialColor") = "blue" }
if (OfficialColor=="undefined") { //Do nothing. Just leave the color alone. }
Application.Unlock()
%>
<BODY BGCOLOR="<%=Application("OfficialColor")%>">
<STRONG>
The official application color is <%=Application("OfficialColor")%>.<BR>
</STRONG>
</BODY>
</HTML>
Application Collections:
The two collections are Contents and StaticObjects. StaticObjects come in the form of the <OBJECT> flag. That's done in the global.asa that we saw in Lesson 09. I'll demonstrate it again down below.
By contrast, the Contents collection is demonstrated above. It allows you to set and retrieve variables with Application scope. The format for setting an Application variable is
Share the Variable:
One last thought on Application Variables. The application variable is shared by all visitors. Let's say that you and I are on the same ASP web site at the same time. If you set the background color to white in script11.asp, then I will see "white" as the official color if I go directly to script11a.asp. Application Variables are by no means the most efficient means of passing information from one user to another.
No Apartment Model:
You may notice that the example above seems to be inefficient. Why not just directly assign Application("OfficialColor") = Request.Form("OfficialColor")? Because we can't. By design, the newer (and updated) versions of Microsoft server software intentionally do not support Apartment Model Behavior.
Application Methods:
The two Application Methods are Lock() and Unlock(). Lock() blocks all other users from changing the Application variables. Unlock() releases control so that other users can change it. That's important on a larger site where multiple users may be trying to access the same page at the same time.
Application Events:
The two Application events are Application_OnStart() and Application_OnEnd(). These events are accessed in the global.asa. Let's repeat that script from lesson 09.
<OBJECT RUNAT=Server SCOPE=Session ID=MyInfo PROGID="MSWC.MyInfo">
</OBJECT>
<SCRIPT RUNAT="Server" LANGUAGE="JavaScript">
function Application_OnStart() { Application("someVariableName")="some value" }
function Application_OnEnd() { Application.Contents.RemoveAll() }
function Session_OnStart() { Session.Timeout=15 }
function Session_OnEnd() { //Do Nothing }
</SCRIPT>
<!-- METADATA TYPE="typelib"
FILE="C:\Program Files\Common Files\System\ado\msado15.dll"
-->
Misc. Items:
Application.Contents has two methods of its own.
You'll notice there are also Session Events in the global.asa. We'll deal with those in Lesson 12. You'll also notice a call to the ADO Library. We'll talk about that when we get to databases.
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