在Dapper中从SQL映射OUT

在不使用Dapper的情况下,此代码返回正确的“true”结果:

using(connection= new SqlConnection(connectionString))
{
    using(var cmd = connection.CreateCommand())
    {
        cmd.CommandText= query;
        cmd.CommandType= CommandType.StoredProcedure;
        cmd.CommandTimeout = commandTimeout;

        var pDeviceId = new SqlParameter
        {
            ParameterName = "@DeviceId",
            DbType = DbType.String,
            Size = 150,
            Direction = ParameterDirection.Input,
            Value = parameter.DeviceId
        };
        cmd.Parameters.Add(pDeviceId);

        var pResponse = new SqlParameter
        {
            ParameterName = "@Response",
            DbType = DbType.Boolean,
            Direction = ParameterDirection.Output,
        };
        cmd.Parameters.Add(pResponse);

        await connection.OpenAsync();

        int i = cmd.ExecuteNonQuery();
        var response = (bool)cmd.Parameters["@Response"].Value;

        return response;
    }
}

但是在使用Dapper时,我无法使此代码正常工作。它总是返回一个值“False”:

using (connection = new SqlConnection(connectionString))
{
    using(var cmd = connection.CreateCommand())
    {
        var parameters = new DynamicParameters();
        parameters.Add("@DeviceId", parameter.DeviceId);
        parameters.Add("@Response", dbType: DbType.Boolean, direction: ParameterDirection.Output);

        var reply = (await connection.QueryAsync<bool>(
            query,
            param: parameters,
            commandType: System.Data.CommandType.StoredProcedure).ConfigureAwait(false)).FirstOrDefault();
        return reply;
    }
}

按照永顺的解决方案

var parameters = new DynamicParameters();
                    parameters.Add("@DeviceId", parameter.DeviceId);
                    parameters.Add("@Response", dbType: DbType.Boolean, direction: ParameterDirection.Output);

                    var reply = (await connection.QueryAsync<bool>(
                        query,
                        param: parameters,
                        commandType: System.Data.CommandType.StoredProcedure).ConfigureAwait(false)).FirstOrDefault();
                    return parameters.Get<bool>("@Response");

非常感谢。