Value from the App Settings configuration (app.config / web.config)

Platforms Supported:Limited (.NET Framework only, when using .NET Core then${configsetting} can be used to read values fromappsettings.json-file)

Introduced with NLog 3.0 and with NLog 4.6+ it was included in default NLog-package without needingNLog.Extended.

${appsetting:item=String:default=String}

• item - Key in the apps setting. Required

  Introduced with NLog v4.5, and replaces theName-option.

• Default - Default value if not present. Optional.

Example .config

<configuration>  <appSettings>    <addkey="MyKey"value="MyApplication" />  </appSettings></configuration>

Example renderer: producesMyApplication is this case:

${appsetting:item=MyKey:default=mydefault}

Example#2 renderer: producesmydefault is this case:

${appsetting:item=MyKey2:default=mydefault}

Introduced with NLog 4.6.5

<configuration>  <appSettings>    <addkey="MyKey"value="MyApplication" />  </appSettings>  <connectionStrings>    <addname="ElasticUrl"connectionString="http://localhost:9200"/>  </connectionStrings></configuration>

Example#3 renderer: produceshttp://localhost:9200 is this case:

${appsetting:item=connectionStrings.ElasticUrl}

Note remember to uninstall/removeNLog.Extended-nuget-package from the application when having upgraded to NLog v4.6.5, else connectionStrings-lookup will not work.