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add Element for appSettings (General Settings Schema) 

Adds a custom application setting as a name/value pair to the collection of application settings.

<add
   key="String name"
   value="String value"
/>

Attributes and Elements

The following sections describe attributes, child elements, and parent elements.

Attributes

Attribute Description

key

Required String attribute.

Specifies the name of the application setting. This attribute is the collection key.

value

Required String attribute.

Specifies the value of the application setting.

Inherited attributes

Optional attributes.

Attributes that are inherited by all section elements. For more information, see General Attributes Inherited by Section Elements.

Child Elements

None.

Parent Elements

Element Description

configuration

Specifies the required root element in every configuration file that is used by the common language runtime and the .NET Framework applications.

system.web

Specifies the root element for the ASP.NET configuration settings in a configuration file and contains configuration elements that configure ASP.NET Web applications and control how the applications behave.

appSettings

Contains custom application settings, such as file paths, XML Web service URLs, or any information that is stored in the .ini file for an application.

Remarks

The add element adds a custom application setting as a name/value pair to the collection of inherited application settings in the appSettings element.

The appSettings element stores custom application configuration information such as file paths, XML Web service URLs, or any information that is stored in the .ini file for an application. The key/value pairs that are specified in the appSettings element can be accessed in code using the ConfigurationSettings class.

Default Configuration

The following default appSettings element is configured in the Machine.config file in the .NET Framework versions 1.0 and 1.1.

<appSettings>
        <add key="XML File Name" value="myXmlFileName.xml" /> 
    </appSettings>

Example

Configuration files that are specified in a file attribute must have appSettings rather than configuration as the root node. The following code is correct for a configuration file that is specified in the file attribute.

<?xml version="1.0" encoding="utf-8" ?>
<appSettings>
<add key="Application1" value="MyApplication1" />
<add key="Setting1" value="MySetting" />
</appSettings>

The following code example shows how to define a custom application setting in a configuration file.

<configuration>
    <appSettings>
        <add key="Application Name" value="MyApplication" />
    </appSettings>
</configuration>

Element Information

Configuration section Handler

AppSettingsSection

Configuration member

Add

Configurable locations

Machine.config

Root-level Web.config

Application-level Web.config

Virtual or physical directory–level Web.config

Requirements

Microsoft Internet Information Services (IIS) version 5.0, 5.1, or 6.0

The .NET Framework version 1.0, 1.1, or 2.0

Microsoft Visual Studio 2003 or Visual Studio 2005

See Also

Reference

appSettings Element (General Settings Schema)
configuration Element (General Settings Schema)
clear Element for appSettings (General Settings Schema)
remove Element for appSettings (General Settings Schema)

Concepts

Securing ASP.NET Configuration
ASP.NET Configuration Scenarios

Other Resources

General Configuration Settings (ASP.NET)
ASP.NET Configuration Settings
ASP.NET Configuration Files