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c#sqlado.netdatasetdataadapter

C# SQL Data Adapter System.Data.StrongTypingException


I get my data from SQL to Dataset with Fill. It's just one table with two columns (CategoryId (int) and CategoryName (varchar)).

When I look at my dataset after fill method, CategoryId Columns seems to be correct. But in the CategoryName I have a System.Data.StrongTypingException.

What could that mean?

Any Ideas?


Solution

  • When you get the value of a row/column in a typed dataset, by default it raises this exception when the value is DBNull. So

    string x = Row.CategoryName;//Raises this exception when CategoryName is null.
    

    You can correct this with the typed dataset designer.
    Set the property "Nullvalue" of the CategroyName column to "(Empty)"