Csharp/CSharp Tutorial/LINQ/Expressions

Cast to BinaryExpression

<source lang="csharp">using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Linq.Expressions; using System.Xml.Linq; class Program {

   static void Main(string[] args)
   {
       Func<int, int> func1 = x => x + 5;
       var result = func1(1);
       Expression<Func<int, int>> expression = func => func + 5;
       var originalDelegate = expression.rupile();
       var three = originalDelegate.Invoke(2);
       BinaryExpression operation = (BinaryExpression)expression.Body;
       Console.WriteLine(operation.NodeType);
   }

}</source>

Cast to ParameterExpression

<source lang="csharp">using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Linq.Expressions; using System.Xml.Linq; class Program {

   static void Main(string[] args)
   {
       Func<int, int> func1 = x => x + 5;
       var result = func1(1);
       Expression<Func<int, int>> expression = func => func + 5;
       var originalDelegate = expression.rupile();
       var three = originalDelegate.Invoke(2);
       ParameterExpression parameter = (ParameterExpression)expression.Parameters[0];
       Console.WriteLine(parameter.Name);
   }

}</source>

Compiled Expression Tree

<source lang="csharp">using System; using System.ruponentModel; using System.Linq.Expressions;

   class CompiledExpressionTree
   {
       static void Main()
       {
           Expression firstArg = Expression.Constant(2);
           Expression secondArg = Expression.Constant(3);
           Expression add = Expression.Add(firstArg, secondArg);
           Func<int> compiled = Expression.Lambda<Func<int>>(add).rupile();
           Console.WriteLine(compiled());
       }
   }</source>

Expression Tree

<source lang="csharp">using System; using System.Linq.Expressions; using System.ruponentModel;

   class MainClass
   {
       static void Main()
       {
           Expression firstArg = Expression.Constant(2);
           Expression secondArg = Expression.Constant(3);
           Expression add = Expression.Add(firstArg, secondArg);
           Console.WriteLine(add);
       }
   }</source>

Lambda Expression To Expression Tree

<source lang="csharp">using System; using System.ruponentModel; using System.Linq.Expressions;

   class MainClass
   {
       static void Main()
       {
           Expression<Func<int>> return5 = () => 5;
           Func<int> compiled = return5.rupile();
           Console.WriteLine(compiled());
       }
   }</source>

Lambda Expression With Parameters To Expression Tree

<source lang="csharp">using System; using System.ruponentModel; using System.Linq.Expressions;

   class MainClass
   {
       static void Main()
       {
           Expression<Func<string, string, bool>> expression = ((x, y) => x.StartsWith(y));
           var compiled = expression.rupile();
           Console.WriteLine(compiled("First", "Second"));
           Console.WriteLine(compiled("First", "Fir"));
       }
   }</source>