Add custom methods to Strong DataSet

[Steve Amey]

Hi all

I have created a strong DataSet using Visual Studio. I have been in to the
DataSet's vb file to have a look at the code and see if I can add things to
it. What I'm after is to create a new method on every DataTable in the
DataSet, this method will be called SelectToTable, as I have the need to
select rows in a current table into another table, and the Select method
only returns an array of data rows. However, any changes that I make are
overwritten the next time I edit and save the DataSet in the designer. Is
there a way to add custom functionality to the DataTables and not have them
overwritten the next time I change something in the designer?

Kind regards,
Steve

 

[stand__sure]

in a separate file, inherit from the class and extend it -- this will give
you the functionality without having the tool overwrite your source

 

[Steve Amey]

Hiya

Thanks for the suggestion. I now have a Class that inherits the DataSet, but
how do I get the methods on the DataTable objects themselves? Sorry if it's
easy, I haven't done stuff like this before. Currently I have the
SelectToTable method on the DataSet, so it can be called like this:

Dim oDataSet As New MyDataSet
oDataSet.SelectToTable(filterExpression)

Whereas I would like the following:

Dim oDataSet As New MyDataSet
oDataSet.MyTable.SelectToTable(filterExpression)

So the function would return a table of the same type, just with records
that match the filterExpression. I know I could pass through a table or
table name to the DataSet method, but I would prefer it if possible on each
of the DataTables in the DataSet.

Thanks for your continued help!

Steve.

 

[David]

Hi all

I have created a strong DataSet using Visual Studio. I have been in to the
DataSet's vb file to have a look at the code and see if I can add things to
it. What I'm after is to create a new method on every DataTable in the
DataSet, this method will be called SelectToTable, as I have the need to
select rows in a current table into another table, and the Select method
only returns an array of data rows. However, any changes that I make are
overwritten the next time I edit and save the DataSet in the designer. Is
there a way to add custom functionality to the DataTables and not have them
overwritten the next time I change something in the designer?

No, there's not. The built-in strongly-typed dataset doesn't provide
the functionality to make this design reasonable, although it would be a
very useful way to do things. it's simple enough to inherit from the
dataset, but as you've found, much more difficult to create a usable
subclass of DataTables or typed rows or such.

There's a bunch of alternatives to the standard DataSet out there that
can do this kind of thing. AGDataSetGenerator is one of the more
popular addins that do this (google for it).