C#: Read only configuration context for sql server

MyContextReadOnly.cs

public partial class MyContextReadOnly : MyContext
{
	private readonly string _connectionString = null;

	public MyContextReadOnly(DbContextOptions<MyContextReadOnly> options) : base(options)
	{
		var sqlServerOptionsExtension = options.FindExtension<SqlServerOptionsExtension>()!;
		_connectionString = sqlServerOptionsExtension?.ConnectionString!;
	}

	protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
	{
		base.OnConfiguring(optionsBuilder);

		if (!string.IsNullOrWhiteSpace(_connectionString))
		{
			var builder = new DbConnectionStringBuilder
			{
				ConnectionString = _connectionString
			};
			builder["ApplicationIntent"] = "ReadOnly";
			optionsBuilder.UseSqlServer(builder.ConnectionString);
		}
	}
}