ExecuteNonQueryAsync hangs in MVC app - sql

Question

I have a DAL project I call from my MVC controller. I pass the method a list of objects I want updated. I added break points and it gets to ExecuteNonQueryAsync() and then just hangs. The website keeps "loading" and it never gets to return 1; The query worked before I tried to move it to execute async (you can see where I commented out the execution of the query. I did delete the connection open/close pieces but the query worked fine before this.
Also I updated the code below so I can post it with OBJECT, ListObjects and COL1/COL2 instead of the actual values/object names used.
Thanks in advance!
static async Task<int> NonQuery(System.Data.SqlClient.SqlConnection conn, System.Data.SqlClient.SqlCommand cmd)
{
await conn.OpenAsync();
await cmd.ExecuteNonQueryAsync();
return 1;
}
public static bool updateQuery(List<OBJECT> listObjects)
{
string cnn = System.Configuration.ConfigurationManager.ConnectionStrings["connstring"].ToString();
using (System.Data.SqlClient.SqlConnection mySqlConnection = new System.Data.SqlClient.SqlConnection(cnn))
{
StringBuilder SQLQuery = new StringBuilder();
SQLQuery.AppendLine("UPDATE TABLENAME ");
SQLQuery.AppendLine("SET COL1 = #COL1, ");
SQLQuery.AppendLine("WHERE COL2 = #COL2 ");
//mySqlConnection.Open();
foreach (ObjectType ot in listObjects)
{
System.Data.SqlClient.SqlCommand cmd = new System.Data.SqlClient.SqlCommand(SQLQuery.ToString(), mySqlConnection);
cmd.Parameters.Add("#COL1", System.Data.SqlDbType.Int).Value = COL1VALUE;
cmd.Parameters.Add("#COL2", System.Data.SqlDbType.Int).Value = COL2VALUE;
int result = NonQuery(mySqlConnection, cmd).Result;
//cmd.ExecuteNonQuery();
}
//mySqlConnection.Close();
}

Answer 1

As I describe on my blog, this is a common problem when converting your code to async. The proper solution is to replace all Result and Wait calls with await, as such:
public static async Task<bool> updateQueryAsync(List<OBJECT> listObjects)
{
...
int result = await NonQueryAsync(mySqlConnection, cmd);
...
}
static async Task<int> NonQueryAsync(SqlConnection conn, SqlCommand cmd)
I also changed your async methods to end in Async, as specified by the TAP documentation.