In this article, we learn Try .. Catch and Final Statement.
First , I describe Try,Catch anfd final?
Try: It contains code that may cause exception , The block executes until an exception is thrown or it is completed successfully
catch: it can be used without arguments to catch any type of exception.
Final: it is useful for cleaning up any resources allocated in the try block.
Where to use throw statement?
throw statement can be used in the Catch Block.
what is mean by throw?
used to signal the occurrence of an exception during the Program execution.
which class is using for Thrown Execution?
System.Exception.
Now , we go to Project section.
First, we learn Try catch Block statement.
Project Description:
Loading text file in the Application
Create a Project in the C#.net.
Project Name is Sample Application for TRY CATCH FINAL Statement.
In this Project , We have 2 Forms ,2 Class Files.
In that 2 Forms,
One Form name is frmtrycatchfinal (It creates when Developer creates a Project)
Another Form Name is frmDisplay.
One Class file :Program.cs (it creates when Developer creates a Project.)
Another class file:FileProcessing.cs.
Controls
Names
Menustrip
mnuforApplicaiton
Toolstripmenus
tryCatchToolStripMenu
Toolstripmenus
tryCatchFinalToolStripMenu
Controls in frmDisplay
Controls
Names
Button
btnProcessing
RichTextBox
RichTextBox1
Coding in FileProcessing.cs
Namespace:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;
using System.Windows.Forms;
public static void readingFileusingTryCatch(string filePath,System.Windows.Forms.RichTextBox rtb)
{
try
{
string text = File.ReadAllText(filePath);
rtb.Text = text;
}
catch (System.Exception e)
{
MessageBox.Show(e.Message);
}
}
public static void readingFileusingTryCatchFinal(string filePath, System.Windows.Forms.RichTextBox rtb)
{
try
{
string text = File.ReadAllText(filePath);
rtb.Text = text;
}
catch (System.Exception e)
{
MessageBox.Show(e.Message);
}
finally
{
MessageBox.Show("File Closed");
}
}
Coding in frmtrycatchfinal.cs:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.IO;
public static string frmName;
private void tryCatchToolStripMenuItem_Click(object sender, EventArgs e)
{
frmName = Convert.ToString(frmNames.TryCatchExample);
frmDispaly frm = new frmDispaly();
frm.Show();
}
private void tryCatchFinalToolStripMenuItem_Click(object sender, EventArgs e)
{
frmName = Convert.ToString(frmNames.TryCatchFinalExample);
frmDispaly frm = new frmDispaly(); frm.Show();
}
public enum frmNames { TryCatchExample, TryCatchFinalExample }
Coding in frmDisplay.cs
private void frmDispaly_Load(object sender, EventArgs e)
{
this.Text = frmtrycatchfinal.frmName;
}
private void btnProceiing_Click(object sender, EventArgs e)
{
if (this.Text == Convert.ToString(frmtrycatchfinal.frmNames.TryCatchExample))
{
string str = @"C:\text.txt";
FileProcessing.readingFileusingTryCatch(str, richTextBox1);
}
else if (this.Text == Convert.ToString(frmtrycatchfinal.frmNames.TryCatchFinalExample))
{
string str = @"C:\text.txt"; FileProcessing.readingFileusingTryCatchFinal(str, richTextBox1);
}
}
FileProcessing.readingFileusingTryCatch :
It just throws the exception.
In our Project : we see the MessageBox Content like this (Could not find the "C:\text.txt");
FileProcessing.readingFileusingTryCatchFinal:
It just throws the exception and also release the resources in the Final Boxl.
In our Project : MessageBox will show like this (Could not find the "C:\text.txt") and also MessageBox will Show like this ("File Closed")
Conclusion:
I think, you have an Idea about TRY CATCH FINAL Statement.Thanks for reading this Articles .Please any feedback naraayanan1983@gmail.Com.
