C# : Predicate, Func, Action syntaxes

Bringing something out from my personal study material…

I have seen many people getting confused in C# Func, Predicate and Actions just because of the different syntactical ways of using them. Unfortunately, I am too not the exception.:-(

So I thought to bring all the styles at one place…

1.       Func

 Func performs some operation and returns something.

      Syntaxes:

List<string> FruitNames = new List<string>() { "Apple", "Mango", "Pinaple", "Orange" }; //Func syntax 1: using lambada Expression var func1 = FruitNames.Select((x) => x + " is sugary."); //Func syntax 2: using anonymous function(delegate) var func2 = FruitNames.Select(delegate(string x) {      return x + " is sugary."; }); //Func syntax 3: using Func declaration with anonymous function(delegate) var func3 = FruitNames.Select(new Func<string, string>(delegate(string x) {      return x + " is sugary."; }));

2.       Predicate

Predicate performs some operation and returns bool. It is nothing but Func always returning bool. Syntaxes:

List<string> FruitNames = new List<string>() { "Apple", "Mango", "Pinaple", "Orange" }; //Predicate syntax 1: using lambada Expression var predicate1 = FruitNames.Find(x => x.ToLower().StartsWith("a")); //Predicate syntax 2: using anonymous function(delegate) var predicate2 = FruitNames.Find(delegate(string x) {      return x.ToLower().StartsWith("a"); }); //Predicate syntax 3: using Func declaration with anonymous function(delegate) var predicate3 = FruitNames.Find(new Predicate<string>(delegate(string x) {      return x.ToLower().StartsWith("a"); }));

3.       Action

 Action performs some operation and returns nothing.

 Syntaxes:   

List<string> FruitNames = new List<string>() { "Apple", "Mango", "Pinaple", "Orange" }; //Action syntax 1: using lambada Expression FruitNames.ForEach((x) => Console.WriteLine(x + " is sugary.")); //Func syntax 2: using anonymous function(delegate) FruitNames.ForEach(delegate(string x) {      Console.WriteLine(x + " is sugary."); }); //Func syntax 3: using Func declaration with anonymous function(delegate) FruitNames.ForEach(new Action<string>(delegate(string x) {      Console.WriteLine(x + " is sugary."); }));

So…go and use them…they do wonders to the code….

As a SharePoint Professional, I sometimes feel little low because SharePoint’s future lies in OOB approach with very little coding opportunities. :-( Very interesting to see how fast C# language is getting evolved with every new .net framework release where .net framework itself getting richer and richer...Need enough time, patience, focus and motivation to explore those. I should keep on trying with my little brain....