Csharp/C Sharp/LINQ/var

An Anonymous Type Assigned to a Variable Declared with the var Keyword

<source lang="csharp">

using System; public class MainClass {

   public static void Main() {
       var unnamedTypeVar = new { firstArg = 1, secondArg = "Joe" };
       Console.WriteLine(unnamedTypeVar.firstArg + ". " + unnamedTypeVar.secondArg);
   }

}

</source>

An Example of Collection Initialization

<source lang="csharp">

using System.Collections.Generic; using System; public class MainClass {

   public static void Main() {
       List<string> presidents = new List<string> { "AAAA", "BBBBBB", "CCCCCCCC" };
       foreach (string president in presidents) {
           Console.WriteLine(president);
       }
   }

}

</source>

Anonymous Types

<source lang="csharp"> using System; using System.Collections.Generic; using System.Diagnostics; class MainClass{

   static void DisplayProcesses(Func<Process, Boolean> match) {
       var processes = new List<Object>();
       foreach (var process in Process.GetProcesses()) {
           if (match(process)) {
               processes.Add(new {
                   process.Id, Name = process.ProcessName,
                   Memory = process.WorkingSet64
               });
           }
       }
   }
   static void Main(string[] args) {
       DisplayProcesses(process => process.WorkingSet64 >= 20 * 1024 * 1024);
   }

}

</source>

Instantiating and Initializing an Anonymous Type Using Object Initialization

<source lang="csharp">

using System; public class MainClass {

   public static void Main() {
       var address = new {
           address = "First Street",
           city = "Vancouver",
           state = "GA",
           postalCode = "99999"
       };
       Console.WriteLine("address = {0} : city = {1} : state = {2} : zip = {3}",
        address.address, address.city, address.state, address.postalCode);
       Console.WriteLine("{0}", address.GetType().ToString());
   }

}

</source>

Using var

<source lang="csharp"> using System; using System.Collections.Generic; using System.Diagnostics; class MyPC {

   public Int32 Id { get; set; }
   public Int64 Memory { get; set; }
   public String Name { get; set; }

} class LanguageFeatures {

   static void Main(string[] args) {
       var processes = new List<MyPC>();
       foreach (var process in Process.GetProcesses()) {
           var data = new MyPC();
           data.Id = process.Id;
           data.Name = process.ProcessName;
           data.Memory = process.WorkingSet64;
           processes.Add(data);
       }
       Console.Write(processes);
   }

}

</source>