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c#jsonvb.netdynamiclambda

error CS1977: Cannot use a lambda expression as an argument to a dynamically dispatched operation


I've converted some code from vb.net to c# but it's having problems with a lambda.

error CS1977: Cannot use a lambda expression as an argument to a dynamically dispatched operation without first casting it to a delegate or expression tree type.

Here's the translated code..

dynamic ds = (JArray)o["Tables"][0]["Rows"];
using(var connection = new SqlConnection(cnnString))
    {connection.Open();
     ds.Select(ja =>
        connection.Execute("INSERT INTO dbo.AddPlay(UserId, Timestamp, YoutubeId, Source, PlayCount, Rating) " + 
                " VALUES(ja(0).Value<string>(), ja(1).Value<string>() ja(2).Value<string>(), ja(3).Value<string>(), GetInt(ja(4)), GetInt(ja(5)))"));
    }

Solution

  • Using a foreach and creating a parameterized SqlCommand is best practice

    var ds = (JArray)o["Tables"][0]["Rows"];
    
    using (var connection = new SqlConnection(cnnString)) {
        connection.Open();
        var cmdIns = new SqlCommand("INSERT INTO dbo.AddPlay(UserId, Timestamp, YoutubeId, Source, PlayCount, Rating) VALUES(@UserId, @Timestamp, @YoutubeId, @Source, @PlayCount, @Rating)", connection);
        cmdIns.Parameters.Add("@UserId", SqlDbType.VarChar, 20);
        cmdIns.Parameters.Add("@Timestamp", SqlDbType.VarChar, 20);
        cmdIns.Parameters.Add("@YoutubeId", SqlDbType.VarChar, 20);
        cmdIns.Parameters.Add("@Source", SqlDbType.VarChar, 20);
        cmdIns.Parameters.Add("@PlayCount", SqlDbType.Int);
        cmdIns.Parameters.Add("@Rating", SqlDbType.Int);
    
        foreach (var ja in ds) {
            cmdIns.Parameters["@UserId"].Value = ja[0].Value<string>();
            cmdIns.Parameters["@Timestamp"].Value = ja[1].Value<string>();
            cmdIns.Parameters["@YoutubeId"].Value = ja[2].Value<string>();
            cmdIns.Parameters["@Source"].Value = ja[3].Value<string>();
            cmdIns.Parameters["@PlayCount"].Value = GetInt(ja[4]);
            cmdIns.Parameters["@Rating"].Value = GetInt(ja[5]);
    
            cmdIns.ExecuteNonQuery();
        }
    }