Looping through Dapper.Net query results without the use of models

Question

I am still new to C# and I am struggling to find a solution to my problem. My SQL dapper query returns a table (based on my understanding though it is not really a table if it is IEnumerable unlike what I am use to working with ADO and recordsets) with three columns col1, col2, and col3 and has multiple rows. I need to loop through this query result for each row and test the values (ie, a foreach loop where I check row(0).field1=5, row(1).field1 = 5 for each row, etc) do what I need to do. This seems so basic but I all the dapper tutorials I see do not show examples for this and if they do they seem to utilize class objects rather than accessing the results directly (if thats even possible or do you have to map the results to a model?) My code is as follows:

                String query = "exec dbo.storeProcedure @jsonData, @mainDocJSON, @supportingDocsJSON";

            IEnumerable queryResult;

            using (var connection = new SqlConnection(connectionString))
            {
                queryResult = connection.Query(query, new { jsonData = jsonData, mainDocJSON = mainDocJSON, supportingDocsJSON = supportingDocsJSON });
            }

I also end up returning IEnumerable results from the controller this code resides in so I send it back to the user in JSON using the following.

return Ok(queryResult);

Answer 1

connection.Query return a IEnumerable, why dont we create a class to map the set from ? Dapper is a micro-ORM, but still... ORM.

For ex: Your table return 3 column Id, Name, CreatedDate.

// declare a class to map the result first
public class ResultHolderDto
    {
        public int Id { get; set; }
        public string Name { get; set; }
        public DateTime CreatedDate { get; set; }
    }

// query somewhere
// This will return IEnumerable<ResultHolderDto>, feel free to play around as normal
var queryResult = await connection.QueryAsync<ResultHolderDto>(query, new { jsonData = jsonData, mainDocJSON = mainDocJSON, supportingDocsJSON = supportingDocsJSON });

foreach(var item in queryResult)
{
    var col1Value = queryResult.Id;
    var col2Value = queryResult.Name;
    var col3Value = queryResult.CreatedDate;
    // Then do something with col1Value, col2Value, col3Value...
}