Ejemplo n.º 1
0
        static void Main(string[] args)
        {
            Student1 std = null;

            try
            {
                try
                {
                    std.StudentName = "";
                }
                catch
                {
                    Console.WriteLine("Inner catch");
                }
            }
            catch
            {
                Console.WriteLine("Outer catch");
            }
        }
        static void Main1()
        {
            //Here we Subjects property in the Student1 class whichis a collection of strings.
            //Use of Select :
            IEnumerable <List <string> > Subjects1 = Student1.GetAllStudents().Select(stu => stu.Subjects);

            foreach (List <string> subjects in Subjects1)
            {
                foreach (string subject in subjects)
                {
                    Console.WriteLine(subject);
                }
            }

            //Use Of Select Many :
            IEnumerable <string> Subjects2 = Student1.GetAllStudents().SelectMany(stu => stu.Subjects);

            foreach (string subject in Subjects2)
            {
                Console.WriteLine(subject);
            }
        }
        //SelectMany Operator belong to Projection Operators category. It is used to project each element of a sequence to an IEnumerable<T> and flattens the resulting sequences into one sequence.
        static void Main1()
        {
            //Return all the Subject List------------------------------------------------------------------------------------------------------------------------------------------------------------------
            IEnumerable <string> Subjects10 = Student1.GetAllStudents().SelectMany(stu => stu.Subjects); //This will return all the subjects of all the students repeatidly
            IEnumerable <string> Subjects11 = Student1.GetAllStudents().SelectMany(stu => stu.Subjects).Distinct();

            foreach (string subject in Subjects11)
            {
                //Console.WriteLine(subject);
            }

            //Return all the Subjects by using a SQl Query Like Patteren-------------------------------------------------------------------------------------------------------------------------------------
            IEnumerable <string> Subjects20 = from student in Student1.GetAllStudents()
                                              from subject in student.Subjects
                                              select subject;       //This will return all the subjects of all the students repeatidly

            IEnumerable <string> Subjects21 = (from student in Student1.GetAllStudents()
                                               from subject in student.Subjects
                                               select subject).Distinct();       //This will return all the subjects of all the students repeatidly

            foreach (string subject in Subjects21)
            {
                //Console.WriteLine(subject);
            }

            //How we write all the Subjects- Student Name Side by side by using Linq Query----------------------------------------------------------------------------------------------------------------------
            var result30 = Student1.GetAllStudents().SelectMany(stu => stu.Subjects, (student, subject) => new
            {
                StudentName = student.Name,
                SubjectName = subject
            });

            foreach (var v in result30)
            {
                Console.WriteLine("{0} - {1} ", v.StudentName, v.SubjectName);
            }
            Console.WriteLine(result30.Count());

            //How we write all the Subjects- Student Name Side by side by using Sql Like Query--------------------------------------------------------------------------------------------------------------------
            var result31 = from student in Student1.GetAllStudents()
                           from subject in student.Subjects
                           select new { SubjectName = student.Name, StudentName = subject };

            foreach (var v in result31)
            {
                //Console.WriteLine("{0} - {1} ", v.StudentName, v.SubjectName);
            }
            // Console.WriteLine(result31.Count());

            //Write the Alphabet Series and the Numbers in the String Array---------------------------------------------------------------------------------------------------------------------------------------
            String[] stringArray =
            {
                "ABCDEFGHIJKLMNOPQRSTUVWXYZ",
                "0123456789"
            };

            IEnumerable <char> result1 = stringArray.SelectMany(s => s);

            foreach (char c in result1)
            {
                //Console.WriteLine(c);
            }

            //we can also rewrite the above result by using Sql Like Patteren-------------------------------------------------------------------------------------------------------------------------------------
            IEnumerable <char> result2 = from chs in stringArray
                                         from ch in chs
                                         select ch;

            foreach (char ch in result2)
            {
                //Console.WriteLine(ch);
            }
        }