static void Main(string[] args)
{
var students = new List <Student>()
{
new Student(5, "John", "Computer Science"),
new Student(4, "Steve", "Biology"),
new Student(1, "Bill", "Math"),
new Student(4, "Ram", "Math"),
new Student(3, "Ron", "Math"),
new Student(4, "Ram", "Biology"),
};
Func <Student, int> idFunc = (x) => x.ID;
Func <Student, string> nameFunc = (x) => x.Name;
Func <Student, string> classFunc = (x) => x.Class;
//var result = students.OrderBy(x=>idFunc(x)).ThenBy(y=>nameFunc(y));
var result = LINQFunctions.OrderBy(students, x => idFunc(x), new KeyComparer <int>())
.ThenBy(y => nameFunc(y), new KeyComparer <string>())
.ThenBy(z => classFunc(z), new KeyComparer <string>());
foreach (var current in result)
{
Console.WriteLine(current.ID + " : " + current.Name + " : " + current.Class);
}
}
public void TestThenByWithOneCriterion()
{
var students = new List <Student>()
{
new Student(5, "John", "Computer Science"),
new Student(4, "Steve", "Biology"),
new Student(1, "Bill", "Math"),
new Student(4, "Ram", "Math"),
new Student(3, "Ron", "Math"),
new Student(4, "Ram", "Biology"),
};
Func <Student, int> idFunc = (x) => x.ID;
Func <Student, string> nameFunc = (x) => x.Name;
var result = LINQFunctions.OrderBy(students, x => idFunc(x), new KeyComparer <int>()).
ThenBy(y => nameFunc(y), new KeyComparer <string>()).ToList();
Assert.Equal(1, result[0].ID);
Assert.Equal(5, result[5].ID);
Assert.Equal("Steve", result[4].Name);
}
