C# 5.0 Programmer's Reference

Chapter 8 ❘ 645
The query orders its results by both the number of wins and the total number of points. Finally,
it selects the team’s name together with the number of wins and total number of points.
Next, the program loops through the query and displays the results. Because the query
selects simple string and integer values, displaying the results is easy.
6. Example program CreateVolleyballDataSet does this. The code is fairly long, so it isn’t
shown here. Download the example to see the solution.
7. Example program VolleyballTeamsAndPlayersDataSet does this.
The program demonstrates two approaches. The following code shows the first approach.
// Loop through the teams displaying them and their players.
foreach (DataRow team in teamsTable.AsEnumerable())
{
// Display the team's name.
Console.WriteLine(team.Field("TeamName"));
// Select the team's players.
string teamName = team.Field("TeamName");
var players =
from player in playersTable.AsEnumerable()
where player.Field("TeamName") == teamName
select player;
}
// Display the players.
foreach (var player in players)
Console.WriteLine(" " +
player.Field("FirstName") + " " +
player.Field("LastName"));
This code loops through the records from the Teams table. (Note that the items returned
by the table’s AsEnumerable method are DataRow objects. Note also that you could loop
over the table’s Rows collection instead of using AsEnumerable.)
For each team, the program displays the team’s name, selects the corresponding records in
the Players table, and displays the selected players.
The program’s second approach uses the following code.
// Select the teams joined with the players.
var teams =
from team in teamsTable.AsEnumerable()
join player in playersTable.AsEnumerable()
on team.Field("TeamName") equals player.Field("TeamName")
group player by team into teamPlayers
select teamPlayers;
// Loop through the teams displaying them and their players.
foreach (var team in teams)
{
// Display the team's name.
Console.WriteLine(team.Key.Field("TeamName"));
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