Checking if a datatable is null

Question

The following code is what I\'ve been using to retrieve user information from a sql database.

            string userName = LoginUser.UserName;
            strin         


        

Answer 1

As of C# 6.0 you can use the Null conditional operator ?. (or ?[] for arrays).

The null conditional operator simplifies the statement to:

if (dt?.Rows?.Count > 0)

This returns false when:

1. the data table dt is null
2. data table Rows dt.Rows is null
3. the number of rows dt.Rows.Count is 0

Using the null conditional operator you can avoid manually checking both the data table and count properties, eg if (dt != null && dt.Rows.Count > 0)