Get values from Asp.Net Core AppSettings

Question

On an Asp.Net Core 3.1 application I have the following section on AppSettings:

  "Logins": [
    {
      "Name": "Facebook",
      "Id": "fb_id",
      "Secret": "fb_secret"
    },
    {
      "Name": "Google",
      "Id": "go_id",
      "Secret": "go_secret"
    }
  ]

I am trying to get values, such as Id of Facebook, so I tried:

Configuration.GetValue<String>("Logins:Facebook:Id")

But this won't work ... How can I get the values?

Answer 1

All ASP.NET Core configuration gets converted into key-value pairs. In your example, you end up with key-value pairs that looks like this:

• Logins:0:Name = Facebook
• Logins:0:Id = fb_id
• Logins:0:Secret = fb_secret
• Logins:1:Name = Google
• Logins:1:Id = go_id
• Logins:1:Secret = go_secret

As this shows, there's no key named Logins:Facebook:Id , which is because the JSON structure uses an array. If you want to target the providers by name, update the JSON to use the following structure:

"Logins": {
  "Facebook": {
    "Id": "fb_id",
    "Secret": "fb_secret"
  },
  "Google": {
    "Id": "go_id",
    "Secret": "go_secret"
  }
}

This creates the key-value pairs that you expect, eg:

• Logins:Facebook:Id = fb_id
• Logins:Facebook:Secret = fb_secret

Also, because these values are already strings, you can, if you prefer, just use something like this to read the value:

Configuration["Logins:Facebook:Id"]