Use of the Sort () method of the C # ArrayList

Keywords: ArrayList, IComparer, interface, C #

I saw someone on the internet to ask the use of IComparer interface, so wrote a small example, and you share. If there is any shortage, I hope you won't hesitate to correct me

1, build a structure of employees structure
private struct eployee{
public string name;
public int age;
public string sex;
}
2, new 3 "Employees"
Eployee ep1=new Eployee ();
Ep1.name= "Xiao Zhang";
ep1.age=21;
ep1.sex= "Male";
Eployee ep2=new Eployee ();
Ep2.name= "Lao Li";
ep2.age=43;
ep2.sex= "Male";
Eployee ep3=new Eployee ();
Ep3.name= "Shi Shi";
ep3.age=18;
ep3.sex= "Male";
3, add 3 "Employees" to the "Employee List";

ArrayList employeelist=new ArrayList ();
Employeelist.add (EP1);
Employeelist.add (EP2);
Employeelist.add (EP3);

All right, all set. Now I hope that the EmployeeList "employees" are sorted by age.
What do we do?
It's really simple, we don't have to implement a sort of method, bubble or something. ArrayList provides our out-of-the-box sorting method sort ();
It has three overloads, regardless of which one you use, at least you provide a comparer:icomparer to tell the sort method how you sort the employees.
This comparer must implement the interface: System.Collections.IComparer, the interface has only one member function that you need to implement.
The description is as follows:
[Visual Basic]
Function Compare (_
ByVal x as Object, _
ByVal y as Object _
) as Integer
[C #]
int Compare (
Object X,
Object Y
);
[C + +]
int Compare (
object* x,
Object* y
);
[JScript]
function Compare (
X:object,
Y:object
): int;
(You can refer to MSDN)
You know, let's make it happen.
Private class MyEmployeeCompare:System.Collections.IComparer {
public int Compare (object X,object y) {
Return ((Eployee) x). age-((eployee) y). Age;
}

}
Because we compare the age of "employee", so we can safely write the implementation statement
Return ((Eployee) x). age-((eployee) y). Age;

Myemployeecompare employeecompare=new Myemployeecompare ();

OK now we can sort the employees by their age.

Employeelist.sort (Employeecompare);

#结束