C# Program To Copy Content Of One File To Another File By Overwriting Same File Name

Given a file, now our task is to copy data from one file to another file by overwriting the same file name using C#. So we use the following methods to perform this task: 

1. Copy(String, String, Boolean): It is used to copy the content of one file to a new file with overwrite. 

Syntax:

File.Copy(Myfile1, Myfile2, owrite);

Where Myfile1 is the first file, Myfile2 is the second file, and owrite is a boolean variable if the destination file can be overwritten then it is set to true otherwise false.

2. ReadAllText(String): It opens a text file, then reads the data present in it, and after that closes the file. This method will definitely close the file handle even when an exception arises.

File.ReadAllText(Mypath)

Where Mypath is the location of the file that we want to read. It is of String type.

Let's consider the two files in the source and destination folder with the name sai.txt

source(first):

Hello Geeks welcome to c#.

destination(last):

Hello Geeks welcome to java/php.

Now, our task is to overwrite the last file with the source content so we use the following approach.

Approach:

• Declare variable
• Read source and destination file using ReadAllText() method

file = File.ReadAllText("first/sai.TXT");
file = File.ReadAllText("last/sai.TXT");

• Copy the file by overwriting source(first) file with Copy() method

 File.Copy("first/sai.TXT", "last/sai.TXT",true);

• Read source and destination file using ReadAllText() method and display

file = File.ReadAllText("first/sai.TXT");
file = File.ReadAllText("last/sai.TXT");

Example:

// C# program to copy the data of one file to 
// another file by overwriting the same file name
using System;
using System.IO;

class GfG{
    
static void Main()
{
    
    // Declare file name
    string file;
    
    // Content in files before copying
    Console.WriteLine("Before copy:\n");
    file = File.ReadAllText("first/sai.TXT");
    Console.WriteLine("data in first:\n" + file);

    file = File.ReadAllText("last/sai.TXT");
    Console.WriteLine("data in last :\n" + file + "\n\n\n");
    
    // Copy file with overwriting
    File.Copy("first/sai.TXT", "last/sai.TXT", true);

    // Content in files after copying
    Console.WriteLine("After copy:\n");
    file = File.ReadAllText("first/sai.TXT");
    Console.WriteLine("data in first:\n" + file);

    file = File.ReadAllText("last/sai.TXT");
    Console.WriteLine("data in last :\n" + file + "\n\n\n");
}
}

Output:

Before copy:

data in first:
Hello Geeks welcome to c#.
data in last:
Hello Geeks welcome to java/php.

After copy:

data in first:
Hello Geeks welcome to c#.
data in last:
Hello Geeks welcome to c#.