C# 0 The Complete Reference

from

 statement uses 

how

 to range over the 

travelTypes

 array. 

Recall that 

travelTypes

 contains an array of the general travel classifications: air, land, and 

sea. The 

join

 clause joins each travel type with those transports that use that type. For 

example, the type Land is joined with Bicycle, Car, and Train. However, because of the 

into

clause, for each travel type, the 

join

 produces a list of the transports that use that travel 

type. This list is represented by 

lst

. Finally, 

select

 returns an anonymous type that encapsulates 

each value of 

how

 (the travel type) with a list of transports. This is why the two 

foreach

loops shown here are needed to display the results of the query:

foreach(var t in byHow) {

  Console.WriteLine("{0} transportation includes:", t.How);

  foreach(var m in t.Tlist)

    Console.WriteLine("  " + m.Name);

  Console.WriteLine();

}

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The outer loop obtains an object that contains the name of the travel type and the list of the 

transports for that type. The inner loop displays the individual transports.