Detailed explanation of the usage of ASP.NET configuration file Web.config

The example in this article describes the usage of the ASP.NET configuration file Web.config and is shared with everyone for your reference. The specific analysis is as follows:

1. Understanding the Web.config file

The Web.config file is an XML text file, which is used to store the configuration information of the ASP.NET Web application (such as the most commonly used Setting the authentication method for an ASP.NET Web application), which can appear in every directory of the application. When you create a new Web application through VB.NET, a default Web.config file is automatically created in the root directory by default, including default configuration settings, and all subdirectories inherit its configuration settings. If you want to modify the configuration settings of a subdirectory, you can create a new Web.config file in the subdirectory. It can provide configuration information in addition to the configuration information inherited from the parent directory, and can also override or modify settings defined in the parent directory.

Modifications to the Web.config file during runtime can take effect without restarting the service (Note: Exception in the section). Of course the Web.config file is extensible. You can customize new configuration parameters and write configuration section handlers to handle them.

2. web.config configuration file (default configuration settings) All the following codes should be located between and Time, for learning purposes, the following examples have omitted this XML tag

1, section

Function: Configure ASP.NET authentication support (for Windows, Forms , PassPort, None). This element can only be declared at the computer, site, or application level. The element must be used with the section.
Example:
The following example is a form-based authentication configuration site. When a user who is not logged in accesses a webpage that requires authentication, the webpage automatically jumps to the login webpage.

<authentication mode="Forms" > 
  <forms loginUrl="logon.aspx" name=".FormsAuthCookie"/> 
  </authentication>

The element loginUrl represents the name of the login web page, and name represents the cookie name

##2, section

Function: Control client access to URL resources (such as allowing anonymous user access). This element can be declared at any level (computer, site, application, subdirectory, or page). Required in conjunction with the section.

Example: The following example prohibits access by anonymous users



Note: You can use user .identity.name to get the current authenticated user name; you can use the web.Security.FormsAuthentication.RedirectFromLoginPage method to redirect the authenticated user to the page the user just requested. For specific examples, please refer to:
Forms Verification http://XXXXX/websample/dataauth.aspx

3, section

Function: Configure all compilation settings used by ASP.NET. The default debug attribute is "True". It should be set to True after the program is compiled and delivered for use (details are described in the Web.config file, examples are omitted here)

4,

Role: Provide information about custom error messages for ASP.NET applications. It does not apply to errors that occur in XML Web services.

Example: When an error occurs, jump the web page to a customized error page.

<customErrors defaultRedirect="ErrorPage.aspx" mode="RemoteOnly"> 
  </customErrors>

The element defaultRedirect represents the name of the customized error web page. The mode element indicates: Display custom (friendly) information to users who are not running on the local Web server

5, section

Function: Configure ASP.NET HTTP runtime settings . This section can be declared at the computer, site, application, and subdirectory levels.

Example: Control the maximum size of user upload files to 4M, the maximum time to 60 seconds, and the maximum number of requests to 100

<httpRuntime maxRequestLength="4096" executi appRequestQueueLimit="100"/>

6,

Function: Identify pages specific Configuration settings (such as whether to enable session state, view state, whether to detect user input, etc.). can be declared at the computer, site, application, and subdirectory levels.

Example: Do not detect whether there is potentially dangerous data in the content entered by the user in the browser (Note: This item defaults to detection. If you use non-detection, you must encode or verify the user's input). The encrypted view state is checked when the page is posted back from the client to verify that the view state has not been tampered with on the client side. (Note: This item is not verified by default)

<pages buffer="true" enableViewStateMac="true" validateRequest="false"/>

7.

Function: Configure session state settings for the current application (such as setting whether to enable session state, and save session state Location).

<sessionState mode="InProc" cookieless="true" timeout="20"/> 
  </sessionState>

Note:

mode="InProc" means: store session state locally (you can also choose to store it in a remote server or SAL server or disable session state)
cookieless="true "Indicates: If the user's browser does not support cookies, enable session state (default is False)
timeout="20" means: The number of minutes the session can be idle

8,

作用：配置 ASP.NET 跟踪服务，主要用来程序测试判断哪里出错。
示例：以下为Web.config中的默认配置：     
注：
enabled="false"表示不启用跟踪；requestLimit="10"表示指定在服务器上存储的跟踪请求的数目
pageOutput="false"表示只能通过跟踪实用工具访问跟踪输出；
traceMode="SortByTime"表示以处理跟踪的顺序来显示跟踪信息
localOnly="true" 表示跟踪查看器 (trace.axd) 只用于宿主 Web 服务器

三、自定义Web.config文件配置节

自定义Web.config文件配置节过程分为两步。
一是在在配置文件顶部 和 标记之间声明配置节的名称和处理该节中配置数据的 .NET Framework 类的名称。
二是在 区域之后为声明的节做实际的配置设置。
示例：创建一个节存储数据库连接字符串

<configuration> 
  　<configSections> 
  　<section name="appSettings" type="System.Configuration.NameValueFileSectionHandler, System, Version=1.0.3300.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"/> 
  </configSections> 
  　<appSettings> 
  　　<add key="scon" value="server=a;database=northwind;uid=sa;pwd=123"/> 
  　</appSettings> 
  　<system.web> 
  　　...... 
  　</system.web> 
  </configuration>

四、访问Web.config文件

你可以通过使用ConfigurationSettings.AppSettings 静态字符串集合来访问 Web.config 文件示例：获取上面例子中建立的连接字符串。

希望本文所述对大家的asp.net程序设计有所帮助。

更多ASP.NET配置文件Web.config用法详解相关文章请关注PHP中文网！