Go Program to Convert a String to Uppercase

Introduction

Converting a string to uppercase involves changing all the lowercase letters in the string to their corresponding uppercase letters. This is a common task in text processing. This guide will demonstrate how to write a Go program that converts a given string to uppercase.

Problem Statement

Create a Go program that:

Prompts the user to enter a string.
Converts the string to uppercase.
Displays the uppercase string.

Example:

Input: "Hello, World!"
Output: "HELLO, WORLD!"

Solution Steps

Import the fmt and strings Packages: Use import "fmt" and import "strings" to include the fmt package for formatted I/O operations and the strings package for string manipulation.
Write the Main Function: Define the main function, which is the entry point of every Go program.
Input the String: Use fmt.Scanln or fmt.Scanf to take input from the user for the string.
Convert the String to Uppercase: Use the strings.ToUpper function to convert the string to uppercase.
Display the Uppercase String: Use fmt.Println to display the uppercase string.

Go Program

package main

import (
    "fmt"
    "strings"
)

/**
 * Go Program to Convert a String to Uppercase
 * Author: https://www.javaguides.net/
 */
func main() {
    // Step 1: Declare a variable to hold the input string
    var input string

    // Step 2: Prompt the user to enter a string
    fmt.Print("Enter a string: ")
    fmt.Scanln(&input)

    // Step 3: Convert the string to uppercase using the strings.ToUpper function
    uppercase := strings.ToUpper(input)

    // Step 4: Display the uppercase string
    fmt.Println("Uppercase string:", uppercase)
}

Explanation

Step 1: Declare Variables

The variable input is declared to store the user’s input string.

Step 2: Input the String

The program prompts the user to enter a string using fmt.Print. The fmt.Scanln function reads the input and stores it in the input variable.

Step 3: Convert the String to Uppercase

The strings.ToUpper function is used to convert the input string to uppercase. This function changes all lowercase letters to their corresponding uppercase letters and leaves other characters unchanged.

Step 4: Display the Uppercase String

The program prints the uppercase string using fmt.Println.

Output Example

Example 1:

Enter a string: Hello, World!
Uppercase string: HELLO, WORLD!

Example 2:

Enter a string: goLang is fun
Uppercase string: GOLANG IS FUN

Conclusion

This Go program demonstrates how to convert a string to uppercase using the strings.ToUpper function. It covers basic programming concepts such as string manipulation and input/output operations. This example is useful for beginners learning Go programming and understanding how to work with strings and modify their content.