what is the correct way to read from a datarow if the cell might be null

c# null datarow
leora picture leora · Nov 21, 2009 · Viewed 9.3k times · Source

I have the following code which seems to blow up if the column in the datarow (dr) is null. what is the correct way to parse out the value from the data row and handle null checks?

Person person = new Person()
{
    FirstName = dr["FirstName"].ToString(),
    LastName = dr["LastName"].ToString(),
    BusinessPhoneNumber = dr["BusinessPhone"].ToString(),

Answer

João Angelo picture João Angelo · Nov 21, 2009

If the column is of type string, but is nullable, what about trying:

// FirstName must allow null
FirstName = dr["FirstName"] as string

or

// FirstName would be empty for a NULL in the database
FirstName = (dr["FirstName"] as string) ?? string.Empty

Related questions

Check if DataRow exists by column name in c#?

I want to do something like this: private User PopulateUsersList(DataRow row) { Users user = new Users(); user.Id = int.Parse(row["US_ID"].ToString()); if (row["US_OTHERFRIEND"] != null) { user.OtherFriend = row["US_OTHERFRIEND"].ToString(); } return user; } However, I get …

Read More
How to check if Datarow value is null

Tell me please is this is correct way to check NULL in DataRow if need to return a string Convert.ToString(row["Int64_id"] ?? "") Or should be like check with DBNull.Value. Need to so much more smaller than if(…

Read More
C# DataTable ItemArray returns '{}' - how can I test for null value?

I have a DataTable resultSet; - I'm trying to check fields for null, but get an '{}' (empty-set ?) object back. Searches involving "{}" aren't yielding any appropriate solutions. This is the code that isn't working as expected when the "fk_…

Read More