SkipWhile

In this chapter you will learn:

How to use SkipWhile operator
SkipWhile with filter delegate
SkipWhile and logic operator
Filter by index

Get to know SkipWhile operator

SkipWhile enumerates the input sequence, ignoring each item until the given predicate is false.

It then emits the remaining elements:

using System;/*from j  a  va 2 s .co m*/
using System.Collections;
using System.Collections.Generic;
using System.Linq;

class Program
{
    static void Main()
    {
        int[] numbers = { 3, 5, 2, 7, 4, 1 };

        var skipWhileSmall = numbers.SkipWhile(n => n < 5);
          
        foreach(int s in skipWhileSmall){
           Console.WriteLine(s);
        }
    }
}

The output:

SkipWhile with filter delegate

using System;/* ja v  a  2s  . c o  m*/
using System.Collections;
using System.Collections.Generic;
using System.Linq;

class Program
{
    static void Main()
    {
        string[] names = { "Java", "C#", "Javascript", "SQL", 
          "Oracle", "Python", "C++", "C", "HTML", "CSS" };

        IEnumerable<string> query = names.SkipWhile(n => n.Length < 5);
        foreach(String s in query){
           Console.WriteLine(s);
        }
    }
}

The output:

SkipWhile and logic operator

using System;//from ja  v  a 2  s . com
using System.Linq;
using System.Collections;
using System.Collections.Generic;
public class MainClass {
    public static void Main() {
        string[] presidents = {"ant", "arding", "arrison", "Hayes", "Hoover", "ackson"};
        IEnumerable<string> items = presidents.SkipWhile((s, i) => s.Length > 4 && i < 10);
        foreach (string item in items)
            Console.WriteLine(item);
    }
}

Filter by index

using System;/*from   jav  a2 s  .c om*/
using System.Collections.Generic;
using System.Linq;
using System.Text;

public class MainClass{
   public static void Main() {

       int[] numbers = { 5, 4, 8, 6, 7, 2, 0 };
       
       var laterNumbers = numbers.SkipWhile((n, index) => n >= index);
       
       Console.WriteLine("All elements starting from first element less than its position:");
       foreach (var n in laterNumbers) {
           Console.WriteLine(n);
       }
   }

}

Next chapter...

What you will learn in the next chapter: