Migrating Configuration From ASP.NET MVC 5 to MVC

旧城等待， 2022-07-25 15:37 90阅读 0赞

相关阅读：[http://blog.developers.ba/read-config-file-in-asp-net-vnext/][http_blog.developers.ba_read-config-file-in-asp-net-vnext]

原文：[http://aspnetmvc.readthedocs.org/projects/mvc/en/latest/migration/migratingconfig.html][http_aspnetmvc.readthedocs.org_projects_mvc_en_latest_migration_migratingconfig.html]

By [Steve Smith][], [Scott Addie][]

In the previous article, we began [migrating an ASP.NET MVC 5 project to MVC 6][]. In this article, we migrate the configuration feature from ASP.NET MVC 5 to ASP.NET MVC 6.

In this article:

*  [Setup Configuration][]
 *  [Migrate Configuration Settings from web.config][]
 *  [Summary][]

You can download the finished source from the project created in this article [here][].

## [Setup Configuration][Setup Configuration 1] ##

ASP.NET 5 and ASP.NET MVC 6 no longer use the Global.asax and web.config files that previous versions of ASP.NET utilized. In earlier versions of ASP.NET, application startup logic was placed in an`Application_StartUp` method within Global.asax. Later, in ASP.NET MVC 5, a Startup.cs file was included in the root of the project; and, it was called using an `OwinStartupAttribute` when the application started. ASP.NET 5 (and ASP.NET MVC 6) have adopted this approach completely, placing all startup logic in the Startup.cs file.

The web.config file has also been replaced in ASP.NET 5. Configuration itself can now be configured, as part of the application startup procedure described in Startup.cs. Configuration can still utilize XML files, but typically ASP.NET 5 projects will place configuration values in a JSON-formatted file, such asappsettings.json. ASP.NET 5’s configuration system can also easily access environment variables, which can provide a more secure and robust location for environment-specific values. This is especially true for secrets like connection strings and API keys that should not be checked into source control.

For this article, we are starting with the partially-migrated ASP.NET MVC 6 project from [the previous article][migrating an ASP.NET MVC 5 project to MVC 6]. To setup configuration using the default MVC 6 settings, add the following constructor and property to the Startup.cs class located in the root of the project:

<table style="border-collapse:collapse; border-spacing:0px"> 
 <tbody style=""> 
 <tr style=""> 
 <td style="vertical-align:top"> 
 <div style=""> 
 <pre style="font-family:Consolas,'Andale Mono WT','Andale Mono','Lucida Console','Lucida Sans Typewriter','DejaVu Sans Mono','Bitstream Vera Sans Mono','Liberation Mono','Nimbus Mono L',Monaco,'Courier New',Courier,monospace; border-right-style:solid; border-right-width:1px; border-right-color:rgb(230,233,234); margin-top:0px; margin-bottom:0px; padding:12px; line-height:1.5; color:rgb(64,64,64); overflow:auto"> 1
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 </div> </td> 
 <td style="vertical-align:top; width:672px"> 
 <div style="border:none; padding:0px; overflow-x:auto; margin:0px; background:none"> 
 <pre style="font-family:Consolas,'Andale Mono WT','Andale Mono','Lucida Console','Lucida Sans Typewriter','DejaVu Sans Mono','Bitstream Vera Sans Mono','Liberation Mono','Nimbus Mono L',Monaco,'Courier New',Courier,monospace; margin-top:0px; margin-bottom:0px; padding:12px; line-height:1.5; overflow:auto; color:rgb(64,64,64)">public Startup(IHostingEnvironment env)
{
 
 // Set up configuration sources.
 var builder = new ConfigurationBuilder()
 .AddJsonFile("appsettings.json")
 .AddEnvironmentVariables();
 Configuration = builder.Build();
}

public IConfigurationRoot Configuration {
 get; set; }
</pre> 
 </div> </td> 
 </tr> 
 </tbody> 
</table>

Note that at this point the Startup.cs file will not compile, as we still need to add the following `using`statement:

using Microsoft.Extensions.Configuration;

Add an appsettings.json file to the root of the project using the appropriate item template:

[![../\_images/add-appsettings-json.png][.._images_add-appsettings-json.png]][.._images_add-appsettings-json.png]

## [Migrate Configuration Settings from web.config][Migrate Configuration Settings from web.config 1] ##

Our ASP.NET MVC 5 project included the required database connection string in web.config, in the`<connectionStrings>` element. In our MVC 6 project, we are going to store this information in theappsettings.json file. Open appsettings.json, and note that it already includes the following:

<table style="border-collapse:collapse; border-spacing:0px"> 
 <tbody style=""> 
 <tr style=""> 
 <td style="vertical-align:top"> 
 <div style=""> 
 <pre style="font-family:Consolas,'Andale Mono WT','Andale Mono','Lucida Console','Lucida Sans Typewriter','DejaVu Sans Mono','Bitstream Vera Sans Mono','Liberation Mono','Nimbus Mono L',Monaco,'Courier New',Courier,monospace; border-right-style:solid; border-right-width:1px; border-right-color:rgb(230,233,234); margin-top:0px; margin-bottom:0px; padding:12px; line-height:1.5; color:rgb(64,64,64); overflow:auto">1
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 </div> </td> 
 <td style="vertical-align:top; width:825px"> 
 <div style="border:none; padding:0px; overflow-x:auto; margin:0px; background:none"> 
 <pre style="font-family:Consolas,'Andale Mono WT','Andale Mono','Lucida Console','Lucida Sans Typewriter','DejaVu Sans Mono','Bitstream Vera Sans Mono','Liberation Mono','Nimbus Mono L',Monaco,'Courier New',Courier,monospace; margin-top:0px; margin-bottom:0px; padding:12px; line-height:1.5; overflow:auto; color:rgb(64,64,64)">{
 
	"Data": {
 
		"DefaultConnection": {
 
			"ConnectionString": "Server=(localdb)\\MSSQLLocalDB;Database=_CHANGE_ME;Trusted_Connection=True;"
		}
	}
}
</pre> 
 </div> </td> 
 </tr> 
 </tbody> 
</table>

In the highlighted line depicted above, change the name of the database from \_CHANGE\_ME. We are going to point to a new database, which will be named NewMvc6Project to match our migrated project name.

## [Summary][Summary 1] ##

ASP.NET 5 places all startup logic for the application in a single file, in which the necessary services and dependencies can be defined and configured. It replaces the web.config file with a flexible configuration feature that can leverage a variety of file formats, such as JSON, as well as environment variables.

[http_blog.developers.ba_read-config-file-in-asp-net-vnext]: http://blog.developers.ba/read-config-file-in-asp-net-vnext/
[http_aspnetmvc.readthedocs.org_projects_mvc_en_latest_migration_migratingconfig.html]: http://aspnetmvc.readthedocs.org/projects/mvc/en/latest/migration/migratingconfig.html
[Steve Smith]: http://ardalis.com/
[Scott Addie]: http://scottaddie.com/
[migrating an ASP.NET MVC 5 project to MVC 6]: http://aspnetmvc.readthedocs.org/projects/mvc/en/latest/migration/migratingfrommvc5.html
[Setup Configuration]: http://aspnetmvc.readthedocs.org/projects/mvc/en/latest/migration/migratingconfig.html#setup-configuration
[Migrate Configuration Settings from web.config]: http://aspnetmvc.readthedocs.org/projects/mvc/en/latest/migration/migratingconfig.html#migrate-configuration-settings-from-web-config
[Summary]: http://aspnetmvc.readthedocs.org/projects/mvc/en/latest/migration/migratingconfig.html#summary
[here]: https://github.com/aspnet/Docs/tree/master/mvc/migration/migratingconfig/samples
[Setup Configuration 1]: http://aspnetmvc.readthedocs.org/projects/mvc/en/latest/migration/migratingconfig.html#id1
[.._images_add-appsettings-json.png]: http://aspnetmvc.readthedocs.org/projects/mvc/en/latest/_images/add-appsettings-json.png
[Migrate Configuration Settings from web.config 1]: http://aspnetmvc.readthedocs.org/projects/mvc/en/latest/migration/migratingconfig.html#id2
[Summary 1]: http://aspnetmvc.readthedocs.org/projects/mvc/en/latest/migration/migratingconfig.html#id3