How to Get connaction string from configuration in a static class?

Question

i have a class that i can get the connaction string from the configuration

public class UserClass
{
    private readonly IConfiguration _configuration;
    public UserClass(IConfiguration configuration, ILogger<UserClass> logger) => _configuration = configuration;

    public bool CheckUserPermissions(string email, string password, bool hashed, string SessionID)
    {
       string strConnString = _configuration.GetConnectionString("DefaultConnection").ToString();
    }
}

in a static class i can't get the configuration.

public static class FunctionClass
{

    public static DataTable GetData()
    {
       string strConnString =  configuration.GetConnectionString("DefaultConnection").ToString();
    }
}

Answer 1

You can't inject any service to the static classes. but if you need to access the connection string in a static class, You have two options:

1:

You can use ConfigurationBuilder :

var config = new ConfigurationBuilder()
            .AddJsonFile(dir) // dir: path to the configuration file
            .Build();
var conStr = config.GetConnectionString("DefaultConnection");

2:

If it is an Asp.net core project, try to read the connection string in the startup class and set your connection string to a static global property/field.

public static class FunctionClass
{
   public static string ConnectionString = "";

// set the ConnectionString value in the startup