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Object cannot be cast from DBNull to other types" (mariadb 10.3)
@kriangkrai kongsamlee, Welcome to Microsoft Q&A, could you provide some c# code with me? I will have a test for it.
@kriangkrai kongsamlee are you still facing the issue? can you please provide more information on the error?
Regards
Geetha
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Hi, I have the same problem. When my C# code wants to make a SQL-connection I the error mentioned:
System.InvalidCastException: 'Object cannot be cast from DBNull to other types.'
Source: "mscorlib"
The problem started when I got a new laptop. Unfortunately the old one is wiped already.
I am not sure if this has anything to do with a column (like in the answer).
What can I do?
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That is correct. when a column value is null, the object DBNull is returned rather than a typed value. You must first test that the column value is not null via the api before accessing as the desired type.
If you use the Connector/NET (i.e., MySql.Data), try using the MySqlConnector instead of MySql.Data.
References:
MySQL Connector fails to connect to MariaDB 10.10.2
MySqlConnection.Open() System.InvalidCastException: Object cannot be cast from DBNull to other types