Find the null value of a Datatable

Question

I am building a AWS lambda function .net core.

The issue I am encountering is, when there is no data in the row / column of the datatable I still get a count of one, in turn getData != null && getData.Count() > 0 defaults true and then throws a NullRefrenceError since the value is null when it goes to the loop, I have tried checking for multiple null types in datatable with them still defaulting to true.

Is there another way to check for nullable values, to avoid the assignment causing the error in a datatable column / row.

public object emailGets ( AType invoiceNum, ILambdaContext context )
        {
         Connection conn = new Connection();

         try 
         {
            string query = "SELECT QUERY";
            conn.getData(query);

                DataRow[] getData = conn.Dt.Select();


            if(getData != null && getData.Count() > 0)
            {

            foreach (var item in getData)
            {
              string yourItem = item.Field<String>("email").ToString();
            }
            return new userData { email = yourItem};
            }
             else 
            {

            return new userEmailAddress { email = null}; 
            }
            
        } catch ( Exception e )
         {
             throw e; 
         }

        }
    }

 public class userEmailAddress
    {
        public string email { get; set; }
    }

Answer 1

ToString() will throw a NullReferenceException when the source is null. So when you do

string yourItem = item.Field<String>("email").ToString();

and the item.Field<String>("email") part returns null, you'll get that exception.

Luckily, that ToString() call is redundant, so you can simply remove it and just have:

string yourItem = item.Field<String>("email");

Keep in mind that yourItem can now be null here.