File.write for writing in Ruby

Introduction

File.write lets you save text or data directly into a file quickly and easily.

You want to save user input into a file.

You need to create a new file with some content.

You want to overwrite an existing file with new data.

You want to log messages or results into a file.

You want to save program output for later use.

Syntax

Ruby

File.write(filename, content, mode: "w")

filename is the name of the file you want to write to.

content is the text or data you want to save inside the file.

Examples

Writes the text "Hello, world!" into a file named hello.txt.

Ruby

File.write("hello.txt", "Hello, world!")

Saves the string "12345" into data.txt, creating the file if it doesn't exist.

Ruby

File.write("data.txt", "12345")

Adds the line "Error occurred" to the end of log.txt without erasing existing content.

Ruby

File.write("log.txt", "Error occurred\n", mode: "a")

Sample Program

This program writes the message "Hi there!" into a file named greeting.txt and then prints a confirmation.

Ruby

filename = "greeting.txt"
message = "Hi there!"
File.write(filename, message)
puts "Saved message to #{filename}"

Important Notes

File.write overwrites the file by default unless you use mode: "a" to append.

If the file does not exist, File.write creates it automatically.

Use \n for new lines inside strings.

Summary

File.write saves text directly into a file quickly.

It creates the file if it doesn't exist and overwrites by default.

You can append to a file by setting mode to "a".