如何查询DataSet并遍历结果？

Question

I have a DataSet which contains two tables, Publication and Owner, which are linked on Publication ID. How do I query the dataset? What I am trying to do is get all of the owners for a particular publication, and then I want to iterate over the resulting set, concatenate the owner names together and populate a label with the information...

But lets begin with, how do i query the dataset?

I also have a DataRelation, can I query that somehow to get the child rows for the current row?

Thanks.

Answer 1

ADO.NET supports two fundamental approaches for performing filtering and sorting of datasets:

The DataTable Select Method - This method is overloaded to accept arguments to filter and sort data rows returning an array of DataRow objects.

The DataView object sort, filter and find methods - This object uses the same filter arguments supported by the Select method, but the DataView exposes structures that can be bound to data-aware controls. See DataView.RowFilter

Iterating over filtered rows is as easy as:

DataTable dt;
...
foreach (DataRow dr in dt.Select(filter))
{
    // ...
}

This article contains several examples: A Practical Guide to .NET DataTables, DataSets and DataGrids - Part 1

Answer 2

You could look into LINQ to Dataset , which allows you to perform queries against DataSets with multiple tables. You can perform joins between the tables on the appropriate columns amongst other things.