Data is Null. This method or property cannot be called on Null values

Question

if (!string.IsNullOrEmpty(rd.GetString(2)))
{
    StrBcc = rd.GetString(2);
}

Error: System.Data.SqlTypes.SqlNullValueException: Data is Null. This method or property cannot be called on Null values.

Answer 1

My solution was to create an extension method:

static class DataReaderExtensions
{
    public static string GetStringNullCheck(this IDataReader reader, int ordinal)
    {
        return reader.IsDBNull(ordinal) ? null : reader.GetString(ordinal);
    }
}

So I can use it as:

 StrBcc = rd.GetStringNullCheck(2);

Answer 2

You should use

if (!rd.IsDBNull(2))
    StrBcc = rd.GetString(2);

That's because when you use string.IsNullOrEmpty(x) you are telling your app that x is a string, while is a database null value, which is different from a string whose value is null.