VS 2019 Set ValidationAttribute value from appsettings.json

[babyekc]

Hi all,

I have this:

[AttributeUsage(AttributeTargets.Property, AllowMultiple = false, Inherited = false)]
    public class PasswordPolicyAttribute : ValidationAttribute
    {
        private readonly int _minimumCharacters;
        private readonly int _maximumCharacters;
        private readonly int _maximumConsecutiveCharacters;
        private readonly bool _requiredUppercase;
        private readonly bool _requiredLowercase;
        private readonly bool _requiredNumericCharacters;
        private readonly bool _requiredSpecialCharacters;

        public PasswordPolicyAttribute(int minimumCharacters = 0,
                                       int maximumCharacters = 0,
                                       int maximumConsecutiveCharacters = 0,
                                       bool requiredUppercase = false,
                                       bool requiredLowercase = false,
                                       bool requiredNumericCharacters = false,
                                       bool requiredSpecialCharacters = false)
        {
            _minimumCharacters = minimumCharacters;
            _maximumCharacters = maximumCharacters;
            _maximumConsecutiveCharacters = maximumConsecutiveCharacters;
            _requiredUppercase = requiredUppercase;
            _requiredLowercase = requiredLowercase;
            _requiredNumericCharacters = requiredNumericCharacters;
            _requiredSpecialCharacters = requiredSpecialCharacters;
        }

and in the ViewModel, i have this:

[PasswordPolicy(3, 10, 3, true, true, true, true)]
public string password_new { get; set; }

and in appsettings.json, i have this:

  "PasswordPolicy": {
    "MinimumCharacters": 2,
    "MaximumCharacters": 2,
    "MaximumConsecutiveCharacters": 2,
    "RequiredUppercase": true,
    "RequiredLowercase": true,
    "RequiredNumericCharacter": true,
    "RequiredSpecialCharacter": true,

how can i read values from appsettings and set the '3, 10, 3, true, true, true, true' ?

 

[NeedSomeAnswers]

Ok so in asp.net core which as your using appsettings.json i assume your using, you read in the settings like this (add this method to your startup.cs)

 private void GetAppSettings(string contentRoot)
        {
            var builder = new ConfigurationBuilder()
            .SetBasePath(contentRoot)
            .AddJsonFile("appsettings.json", optional: false, reloadOnChange: true)
            .AddEnvironmentVariables()
            .AddInMemoryCollection(
                new Dictionary<string, string> {
                    {"Timezone", "+1"}
                });
            Configuration = builder.Build();
        }

You want to call that method in Startup.cs by adding a new constructor method

public Startup(IConfiguration configuration, IWebHostEnvironment env)
        {
            GetAppSettings(env.ContentRootPath);
        }

Once you have read the app setting in you can read them like this to get an individual value

string Settingval = Configuration.GetValue<string>("AppSettings:SettingName")

if you want to read all your app settings into a class than create a class eg

public class PasswordPolicy
{
   public string Settings1{ get; set; }
   public string Settings2{ get; set; }
}

then get the whole section and inject it into your service layer

IConfigurationSection sec = Configuration.GetSection("PasswordPolicy");
services.Configure<PasswordPolicy>(sec);

Now in any controller you can inject your settings into the constructor

public class LoginController : Controller
{
  public LoginController(IOptions<PasswordPolicy> pp)

You can't then apply those settings to the view model as that is static, what you should probably do is do your checks in the controller post method when the login form is submitted.