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I am Getting This Error Object cannot be cast from DBNull to other types. while opening connection in asp.net

What I have tried:

I have tried changing net driver From MYSQL Connector NET 8.0 to MYSQL Connector NET 8.2.0 but did not worked out. Earlier i was working fine, and Now it returing error
Posted
Comments
Richard MacCutchan 23-Dec-23 7:50am    
That suggest thatg you are trying to convert a DBNull element to an integer or something similar. So examine your code to see where it is failing.

1 solution

DBNull is a special type: it represents an "empty value" in database nullable column. When you issue a SELECT request against the database any matching rows that contain an SQL NULL value is returned as an instance of the DBNull Class[^]

Although it represents a NULL value in the DB, it isn't the same as a null value in your coding language - you can't directly cast it to any other type.
I'd suggest writing a generic conversion method similar to this:
C#
public static T ConvertDBValue<T>(object o)
    {
    if (o == null || o == DBNull.Value)
        {
        return default(T);
        }
    else
        {
        return (T)o;
        }
    }
And call that for each DB value you process.
 
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