public static void SaveCollectionInXML(StudentArray studentArray, string filename)
{
XmlSerializer x = new XmlSerializer(studentArray.Students.GetType());
TextWriter writer = new StreamWriter(filename);
x.Serialize(writer, studentArray.Students);
writer.Close();
}
public static StudentArray SearchBySurname(String surname, StudentArray studentArray)
{
var searched = new StudentArray();
if (studentArray.Students != null)
{
var studs = studentArray.Cast <Student>().Where(s => s.Surname.ToLower().Contains(surname.ToLower())).Select(s => s);
foreach (var st in studs)
{
searched.Add(st);
}
return(searched);
}
return(new StudentArray());
}
public static StudentArray RemoveStudents(StudentArray studentArray, StudentArray removing)
{
for (int i = 0; i < removing.Students.Length; i++)
{
for (int j = 0; j < studentArray.Students.Length; j++)
{
if (studentArray.Students[j].Equals(removing.Students[i]))
{
studentArray.DeleteStudentByIndex(j);
}
}
}
return(studentArray);
}
public static StudentArray LoadCollectionFromXML(string filename)
{
XmlSerializer formatter = new XmlSerializer(typeof(Student[]));
using FileStream fs = new FileStream(filename, FileMode.OpenOrCreate);
Student[] newpeople = (Student[])formatter.Deserialize(fs);
Student[] arr = new Student[newpeople.Length];
var studentArray = new StudentArray
{
Students = newpeople,
Empty = newpeople.Length == 0
};
studentArray.RecalculateValues();
return(studentArray);
}
public static StudentArray Search(String predicate, StudentArray studentArray, int category)
{
var searched = new StudentArray();
if (studentArray.Students != null)
{
switch (category)
{
case 0:
{
var studs = from s in studentArray.Students where s.Group.ToLower().Contains(predicate.ToLower()) select s; //отложенное выполнение запроса
foreach (var st in studs)
{
searched.Add(st);
}
break;
}
case 1:
{
var studs = (from s in studentArray.Students where s.Specialty.ToLower().Contains(predicate.ToLower()) select s).ToList(); //принудительное выполнение запроса
foreach (var st in studs)
{
searched.Add(st);
}
break;
}
case 2:
{
var studs = studentArray.Cast <Student>().Where(s => s.Faculty.ToLower().Contains(predicate.ToLower())).Select(s => s); //lambda
foreach (var st in studs)
{
searched.Add(st);
}
break;
}
}
return(searched);
}
return(new StudentArray());
}
public static double CalculateAverageAcademicPerformance(StudentArray studentArray)
{
return((from s in studentArray.Students select s.AcademicPerformance).Average());
}
public static double CalculateAverageAge(StudentArray studentArray)
{
return((from s in studentArray.Students select s.Age).Average());
}