[c#] How do I handle Database Connections with Dapper in .NET?

It was asked about 4 years ago... but anyway, maybe the answer will be useful to someone here:

I do it like this in all the projects. First, I create a base class which contains a few helper methods like this:

public class BaseRepository
{
    protected T QueryFirstOrDefault<T>(string sql, object parameters = null)
    {
        using (var connection = CreateConnection())
        {
            return connection.QueryFirstOrDefault<T>(sql, parameters);
        }
    }

    protected List<T> Query<T>(string sql, object parameters = null)
    {
        using (var connection = CreateConnection())
        {
            return connection.Query<T>(sql, parameters).ToList();
        }
    }

    protected int Execute(string sql, object parameters = null)
    {
        using (var connection = CreateConnection())
        {
            return connection.Execute(sql, parameters);
        }
    }

    // Other Helpers...

    private IDbConnection CreateConnection()
    {
        var connection = new SqlConnection(...);
        // Properly initialize your connection here.
        return connection;
    }
}

And having such a base class I can easily create real repositories without any boilerplate code:

public class AccountsRepository : BaseRepository
{
    public Account GetById(int id)
    {
        return QueryFirstOrDefault<Account>("SELECT * FROM Accounts WHERE Id = @Id", new { id });
    }

    public List<Account> GetAll()
    {
        return Query<Account>("SELECT * FROM Accounts ORDER BY Name");
    }

    // Other methods...
}

So all the code related to Dapper, SqlConnection-s and other database access stuff is located in one place (BaseRepository). All real repositories are clean and simple 1-line methods.

I hope it will help someone.

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