Concept of Batch File

What is Batch File?

• A batch file is a text file containing a sequence of commands that are executed in the Command Prompt (CMD) in Windows. 
• Batch files are saved with the .bat extension. 
• They automate repetitive tasks by executing multiple commands in a specific sequence. 
• They can be used to perform a variety of tasks like file management, automation, system configuration, and more.

How a Batch File Works?

• Execution: When you run a batch file, each line of the file is processed and executed one by one in sequence.
• Batch Script: You can create a batch script by simply writing DOS/Windows commands in a text file, then saving the file with a .bat extension.
• Automation: They are useful for automating tasks such as launching programs, copying files, making backups, or performing system maintenance.

Example of a Simple Batch File:

• Let's say you want to create a batch file that displays a message.

1. Open Notepad.

2. Type the following commands:

@echo off 

echo Hello, This is an example of Batch File! 

dir 

pause

3. Save the file as sample.bat

4. Double-click the file to execute it.

• Explanation:
• @echo off: Hides the commands being executed, only shows the output.
• echo: Prints a message on the screen.
• dir: Lists all files in the current directory.
• pause: Waits for the user to press a key before proceeding.

Basic Commands Used in Batch Files:

1. @echo:

• Controls whether commands are displayed during execution.
• Example:

@echo off 

echo This will be displayed, but not the command itself.

2. echo:

• Displays messages or turns command echoing on or off.
• Syntax: echo [message]
• Example:

echo Hello, this is a batch file.

3. PAUSE:

• Pauses the execution of the batch file and displays the message "Press any key to continue…".
• Example:

pause

4. REM:

• Adds a comment in the batch file. Comments are not executed.
• Example:

rem This is a comment, it will be ignored by the batch file.

5. IF:

• Performs conditional processing in the batch file.
• Syntax: if [condition] [command]
• Example:

if exist "C:\file.txt" echo File exists

6. SET:

• Creates, modifies, or displays environment variables.
• Syntax: set variable=value
• Example:

set name=John 

echo %name%

7. CALL:

• Calls another batch file from within a batch file.
• Syntax: call [batch file]
• Example: 

call sample.bat

Program : Create a batch file to identify given number is ODD or EVEN.

In Notepad:

@echo off

set /p num1=Enter your value : 

set /a ans=num1 %% 2

if %ans%==0 (echo The Number %num1% is Even) else (echo The Number %num1% is Odd)

pause

Output: