(008)：将多个输入联接到一个输出序列

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视频演示：http://u.115.com/file/f2f372f454

可以使用 LINQ 查询来创建包含多个输入序列的元素的输出序列。下面的示例演示如何组合两个内存中的数据结构，但组合来自 XML 或 SQL 或数据集源的数据时可应用相同的原则。假定下面两种类类型：

public class Student{    public string FirstName { get; set; }    public string LastName { get; set; }    public int ID { get; set; }    public string Street { get; set; }    public string City { get; set; }    public List<int> Scores;}public class Teacher{    public string FirstName { get; set; }    public string LastName { get; set; }    public int ID { get; set; }    public string City { get; set; }}

下面的示例演示该查询：

static void Main(string[] args){    // Create the first data source.    List<Student> Students = new List<Student>()    {        new Student {FirstName="Svetlana",            LastName="Omelchenko",             ID=111,             Street="123 Main Street",            City="Seattle",            Scores= new List<int> {97, 92, 81, 60}},        new Student {FirstName="Claire",            LastName="O’Donnell",             ID=112,            Street="124 Main Street",            City="Redmond",            Scores= new List<int> {75, 84, 91, 39}},        new Student {FirstName="Sven",            LastName="Mortensen",            ID=113,            Street="125 Main Street",            City="Lake City",            Scores= new List<int> {88, 94, 65, 91}},    };    // Create the second data source.    List<Teacher> Teachers = new List<Teacher>()    {                        new Teacher {FirstName="Ann", LastName="Beebe", ID=945, City = "Seattle"},        new Teacher {FirstName="Alex", LastName="Robinson", ID=956, City = "Redmond"},        new Teacher {FirstName="Michiyo", LastName="Sato", ID=972, City = "Tacoma"}    };    // Create the query.    var PeopleInSeattle = (from student in Students                           where student.City == "Seattle"                           select student.LastName)                .Concat (from teacher in Teachers                        where teacher.City == "Seattle"                        select teacher.LastName);    Console.WriteLine("The following Students and Teachers live in Seattle:");    // Execute the query.    foreach (var Person in PeopleInSeattle)    {        Console.WriteLine(Person);    }    Console.WriteLine("Press any key to exit.");    Console.ReadKey();}

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