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C# Learning: LINQ 'Hello World'


using System;
using System.Linq;

static class HelloWorld
{
    static void Main()
   {

    string[] words = { "hello", "wonderful", "linq", "beautiful", "world" };

     var shortWords = from word in words where word.Length <= 5
     select word;

       foreach (var word in shortWords)
       Console.WriteLine(word);
   }
}

Old School Version of above hello world,

using System;
static class HelloWorld
{
static void Main()
{
string[] words = new string[] {
"hello", "wonderful", "linq", "beautiful", "world" };
foreach (string word in words)
{
if (word.Length <= 5)
Console.WriteLine(word);
}
}
}

Why LINQ?
As the requirement could be more complicated , as below,

var groups =
from word in words
orderby word ascending
group word by word.Length into lengthGroups
orderby lengthGroups.Key descending
select new {Length=lengthGroups.Key, Words=lengthGroups};








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