"selfless sharing: ASP (eighth)" Read the configuration file (ii) read the custom configuration file

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Brief introduction

We described in reading the configuration file (a) appsettings.json, How to read the Appsettings.json.

But then there is the problem: we are using Startup.cs (such As) to implement the configuration read, there are two problems ① if we define n configuration, whether we want to add here N such a configuration; ② if our configuration doesn't want to write in appsettings.json?

　　

　　

Solve the problem

With the two questions above, let's start by adding a configuration file Siteconfig.json

　　

{
"sitebaseconfig": {
File Upload Path
"fileuppath": "/upload/",
Whether to enable Single-user sign-on
"issinglelogin": "True",
Allow upload of file formats
"attachextension": "gif,jpg,jpeg,png,bmp,rar,zip,doc,docx,xls,xlsx,ppt,pptx,txt,flv,apk,mp4,mpg,ts,mpeg,mp3,bak , PDF ",
Picture Upload max kb
"attachimagesize": 12400
}
}

We are reading the configuration class in the file configuration (a) applicationconfiguration

1 public class ApplicationConfiguration 2     {3         #region attribute member 4  5//         <summary> 6//         File upload path 7
   
    ///</summary> 8 Public         string Fileuppath {get; set;} 9         //<summary>10//whether single-user login is enabled         // /</SUMMARY>12 public         bool Issinglelogin {get; set;} ///<summary>14///         </summary>16 public         string Attachextension { Get Set }17///<summary>18///         image upload maximum KB19//         </summary>20 public         int Attachimagesize {get ; Set }21         #endregion22     }
   

In Project.json buildoptions add "copytooutput": "siteconfig.json", so that the file is compiled automatically copied to the output directory (the default is the bin directory):

　　

Modify the domain layer of the Read file configuration (i) appconfigurtaionservices

public class Appconfigurtaionservices
{
　　　　

Public T getappsettings<t> (string Key) where T:class,new ()
{
iconfiguration config = new Configurationbuilder ()
. Add (new jsonconfigurationsource {path= "siteconfig.json", Reloadonchange=true})
. Build ();

var appconfig= new Servicecollection ()
. AddOptions ()
. Configure<t> (config. GetSection (key))
. Buildserviceprovider ()
. Getservice<ioptions<t>> ()
. Value;

Return appconfig;
}

}

　　

Description: we first created a Configurationbuilder object and registered a jsonconfigurationsource on it. When creating this Jsonconfigurationsource object, in addition to specifying the path to the configuration file ("siteconfig.json"), We also set its Reloadonchange property to True. The meaning of this Reloadonchange property is whether the configuration needs to be reloaded when the content of the original configuration file Changes.

At this point we will find configure<t> (config. GetSection (key)) error:

I looked at the services we had before in Startup. Configure<t> () found that the parameter inside this is a two-overloaded one is the iconfiguration one is system.action<t>

Very puzzled, and finally found that there is less extension class Microsoft.Extensions.Options.ConfigurationExtensions

We've solved this problem by adding this install-package Microsoft.Extensions.Options.ConfigurationExtensions through NuGet, thanks @Artech

Let's test it out:

　　

　　

OK, so the two questions we put forward at the beginning of the article are solved!

"selfless sharing: ASP (eighth)" Read the configuration file (ii) read the custom configuration file