System.FormatException in WriteLine

Question

I'm having a trouble in my code with this exception:

System.FormatException

Additional information: Input string was not in a correct format.

I have two files in my visual studio C# solution:

1. Program.cs:

   using System;
   using System.Collections.Generic;
   using System.Linq;
   using System.Text;
   using System.Threading.Tasks;
   
   namespace EventPubSub
   {
       class Program
       {
           static void Main(string[] args)
           {
               Rectangle rect = new Rectangle();
               // Subscribe to the Changed event
               rect.Changed += new EventHandler(Rectangle_Changed);
               rect.Length = 10;
           }
           static void Rectangle_Changed(object sender, EventArgs e)
           {
               Rectangle rect = (Rectangle)sender;
               Console.WriteLine("Value Changed: Length = { 0}", rect.Length);
           }
       }
   }
   

2. file Rectangle.cs:

   using System;
   using System.Collections.Generic;
   using System.Linq;
   using System.Text;
   using System.Threading.Tasks;
   
   namespace EventPubSub
   {
       class Rectangle
       {
           //Declare an event named Changed of
           //delegate type EventHandler
   
           public event EventHandler Changed;
   
           private double length = 5;
   
           public double Length
           {
               get
               {
                   return length;
               }
               set
               {
                   length = value;
                   //Publish the Changed event
                   Changed(this, EventArgs.Empty);
               }
           }
       }
   }
   

The exception arise when I execute the line: rect.Length = 10;

Answer 1

there is a space between { and 0 in the handler which is leading to the exception