1、筛选数组studentArray，筛选条件是名字中包含‘o’的学生信息,并且年龄大于20，将满足条件的学生信息输出到命令行

class Student{
    public int StudentID { get; set; }
    public String StudentName { get; set; }
    public int Age { get; set; }
}class Program{
    static void Main(string[] args)    {
        Student[] studentArray = { 
            new Student() { StudentID = 1, StudentName = "John", Age = 18 },
            new Student() { StudentID = 2, StudentName = "Steve",  Age = 21 },
            new Student() { StudentID = 3, StudentName = "Bill",  Age = 25 },
            new Student() { StudentID = 4, StudentName = "Ram" , Age = 20 },
            new Student() { StudentID = 5, StudentName = "Ron" , Age = 31 },
            new Student() { StudentID = 6, StudentName = "Chris",  Age = 17 },
            new Student() { StudentID = 7, StudentName = "Rob",Age = 19  },
        };

        //待补全...
    }
}

这里待补全代码如下

var query = from student in studentArray
                    where student.Age >20 && student.StudentName.Contains("o")
                    select student;
        foreach (var s in query)
        {
            Console.WriteLine(s.StudentName);
            Console.WriteLine(s.Age);
        }

2、将数组studentArray排序，要求根据年龄排序，如果年龄相同，根据StudentID排序，将排序后的学生信息输出到命令行

这里由于没有说怎么去排序，所以按照年龄升序，年龄相同按照ID升序

class Student{
    public int StudentID { get; set; }
    public String StudentName { get; set; }
    public int Age { get; set; }
}class Program{
    static void Main(string[] args)    {
        Student[] studentArray = { 
            new Student() { StudentID = 1, StudentName = "John", Age = 18 },
            new Student() { StudentID = 2, StudentName = "Steve",  Age = 21 },
            new Student() { StudentID = 3, StudentName = "Bill",  Age = 25 },
            new Student() { StudentID = 4, StudentName = "Ram" , Age = 21 },
            new Student() { StudentID = 5, StudentName = "Ron" , Age = 31 },
            new Student() { StudentID = 6, StudentName = "Chris",  Age = 17 },
            new Student() { StudentID = 7, StudentName = "Rob",Age = 19  },
        };

        //待补全...
    }
}

待补全代码部分

var query = from student in studentArray
                    orderby student.Age ascending, student.StudentID ascending
                    select student;
        foreach (var s in query)

        {
            Console.WriteLine("{0} {1} {2}",s.StudentID,s.StudentName,s.Age);
        }

3、根据SudentID进行分组，输出SudengtId分别为奇数/偶数的学生信息

class Student{
    public int StudentID { get; set; }
    public String StudentName { get; set; }
    public int Age { get; set; }
}class Program{
    static void Main(string[] args)    {
        Student[] studentArray = { 
            new Student() { StudentID = 1, StudentName = "John", Age = 18 },
            new Student() { StudentID = 2, StudentName = "Steve",  Age = 21 },
            new Student() { StudentID = 3, StudentName = "Bill",  Age = 25 },
            new Student() { StudentID = 4, StudentName = "Ram" , Age = 21 },
            new Student() { StudentID = 5, StudentName = "Ron" , Age = 31 },
            new Student() { StudentID = 6, StudentName = "Chris",  Age = 17 },
            new Student() { StudentID = 7, StudentName = "Rob",Age = 19  },
        };

        //待补全...
    }
}

待补全代码如下

var query = from student in studentArray
                    group student by student.StudentID % 2;
        foreach (var s in query)
        {
            Console.WriteLine(s.Key == 0 ? "偶数" :"奇数");
            foreach (var i in s)
                Console.WriteLine("{0} {1} {2}", i.StudentID, i.StudentName, i.Age);
        }

4、输出sudengtArray信息，要求不输出SudengtID字段，输出SudengtName和Age，其中SudengtName要求根据Gender增加Mr. 和Ms. 前缀

class Student{
    public int StudentID { get; set; }
    public String StudentName { get; set; }
    public int Age { get; set; }
    public String Gender { get; set; }
}class Program{
    static void Main(string[] args)    {
        Student[] studentArray = { 
            new Student() { StudentID = 1, StudentName = "John", Age = 18, Gender = "Male" },
            new Student() { StudentID = 2, StudentName = "Steve",  Age = 21, Gender = "Male" },
            new Student() { StudentID = 3, StudentName = "Bill",  Age = 25, Gender = "Male" },
            new Student() { StudentID = 4, StudentName = "Ram" , Age = 21, Gender = "Male" },
            new Student() { StudentID = 5, StudentName = "Ron" , Age = 31, Gender = "Female" },
            new Student() { StudentID = 6, StudentName = "Chris",  Age = 17, Gender = "Female" },
            new Student() { StudentID = 7, StudentName = "Rob",Age = 19, Gender = "Male"  },
        };

        //待补全...
    }
}

待补全代码如下

var query = from student in studentArray
                    select student;
        foreach (var s in query)
        {
            if (s.Gender != "Male")
            {
                Console.WriteLine("{0} {1} {2}","Ms.",s.StudentName, s.Age);
            }
            else
            {
                Console.WriteLine("{0} {1} {2}", "Mr.",s.StudentName, s.Age);
            }
        }