The C# language uses exceptions to handle errors and other exceptional events. Exceptions are the occurrence of some conditions that changes the normal flow of execution . Exceptions are occurred in situations like your program run out of the memory , file does not exist in the given path , network connections are dropped etc. More specifically for better understanding , we can say it as Runtime Errors occurs during the execution of a program that disrupts the normal flow of instructions

In .NET languages , Structured Exceptions handling is a fundamental part of Common Language Runtime . All exceptions in the Common Language Runtime are derived from a single base class , also you can create your own custom exception classes. You can create an exception class that inherits from Exception class . Creating an exception object and handing it to the runtime system is called throwing an exception.

C# Exception handling uses the try, catch, and finally keywords to attempt actions that may not succeed, to handle failures, and to clean up resources afterwards.

  try
  {
	  //your code here
  }
  Catch (exception type)
  {
	  //your code here
  }

finally

The code in the finally block will execute even if there is no Exceptions. That means if you write a finally block , the code should execute after the execution of try block or catch block.

  try
  {
	  //your code here
  }
  Catch (exception type)
  {
	  //if the exception occurred
	  //your code here
  }
  finally
  {
	  //your code here
  }

From the following CSharp code , you can understand how to use try..catch statements. Here we are going to divide a number by zero .

using System;
using System.Windows.Forms;

namespace WindowsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            try
            {
                int val = 100;
                int div = 0;
                int resultVal;
                resultVal = (val / div);
                MessageBox.Show("The result is  : " + resultVal);
            }
            catch (System.Exception  ex)
            {
                MessageBox.Show("Exception catch here - details  : " + ex.ToString());
            }
            finally
            {
                MessageBox.Show("Enter finally block ");
            }
        }
    }
}