Using the Translation API with C#

1. Overview

Google Cloud Translation API provides a simple programmatic interface for dynamically translating an arbitrary string into any supported language using state-of-the-art Neural Machine Translation. It can also be used to detect language in cases where the source language is unknown.

In this codelab, you will focus on using the Translation API with C#. You will learn how to list available languages, translate text and also detect language of a given text.

What you'll learn

• How to use the Cloud Shell
• How to enable the Translation API
• How to Authenticate API requests
• How to install the Google Cloud client library for C#
• How to list available languages
• How to translate text
• How to detect language

What you'll need

• A Google Cloud Platform Project
• A Browser, such Chrome or Firefox
• Familiarity using C#

Survey

How will you use this tutorial?

Read it through only Read it and complete the exercises

How would you rate your experience with C#?

Novice Intermediate Proficient

How would you rate your experience with using Google Cloud Platform services?

Novice Intermediate Proficient

2. Setup and Requirements

Self-paced environment setup

1. Sign-in to the Google Cloud Console and create a new project or reuse an existing one. If you don't already have a Gmail or Google Workspace account, you must create one.

• The Project name is the display name for this project's participants. It is a character string not used by Google APIs. You can always update it.
• The Project ID is unique across all Google Cloud projects and is immutable (cannot be changed after it has been set). The Cloud Console auto-generates a unique string; usually you don't care what it is. In most codelabs, you'll need to reference your Project ID (typically identified as PROJECT_ID). If you don't like the generated ID, you might generate another random one. Alternatively, you can try your own, and see if it's available. It can't be changed after this step and remains for the duration of the project.
• For your information, there is a third value, a Project Number, which some APIs use. Learn more about all three of these values in the documentation.

Caution: A project ID is globally unique and can't be used by anyone else after you've selected it. You are the only user of that ID. Even if a project is deleted, the ID can't be used again

Note: If you use a Gmail account, you can leave the default location set to No organization. If you use a Google Workspace account, choose a location that makes sense for your organization.

2. Next, you'll need to enable billing in the Cloud Console to use Cloud resources/APIs. Running through this codelab won't cost much, if anything at all. To shut down resources to avoid incurring billing beyond this tutorial, you can delete the resources you created or delete the project. New Google Cloud users are eligible for the $300 USD Free Trial program.

Start Cloud Shell

While Google Cloud can be operated remotely from your laptop, in this codelab you will be using Google Cloud Shell, a command line environment running in the Cloud.

From the Google Cloud Console, click the Cloud Shell icon on the top right toolbar:

It should only take a few moments to provision and connect to the environment. When it is finished, you should see something like this:

This virtual machine is loaded with all the development tools you'll need. It offers a persistent 5GB home directory, and runs on Google Cloud, greatly enhancing network performance and authentication. All of your work in this codelab can be done within a browser. You do not need to install anything.

3. Enable the Translation API

Before you can begin using the Translation API, you must enable the API. You can enable the API by using the following command in the Cloud Shell:

gcloud services enable translate.googleapis.com

Note: If this command ERRORs, check that the current Project ID matches your codelab Project ID.

Use the following command to find the current Project ID being used by Cloud Shell:

gcloud info | grep "project"

If the Project ID is not correct, use the following command to use the correct Project ID:

gcloud config set project <PROJECT_ID>

Replace <PROJECT_ID> with the correct Project ID.

4. Install the Google Cloud Translation API client library for C#

First, create a simple C# console application that you will use to run Translation API samples.

dotnet new console -n TranslationApiDemo

The template "Console Application" was created successfully.
Processing post-creation actions...
...
Restore succeeded.

Next, navigate to TranslationApiDemo folder and add Google.Cloud.Translation.V2 NuGet package to the project:

cd TranslationApiDemo/
dotnet add package Google.Cloud.Translation.V2

info : Adding PackageReference for package 'Google.Cloud.Translation.V2' into project '/home/atameldev/TranslationDemo/TranslationDemo.csproj'.
log  : Restoring packages for /home/atameldev/TranslationDemo/TranslationDemo.csproj...
...
info : PackageReference for package 'Google.Cloud.Translation.V2' version '1.0.0' added to file '/home/atameldev/TranslationDemo/TranslationDemo.csproj'.

Now, you're ready to use the Translation API!

5. List Available Languages

In this section, you will first list all available languages in the Translation API.

First, open the code editor from the top right side of the Cloud Shell:

Navigate to the Program.cs file inside the TranslationApiDemo folder and replace the code with the following:

using System;
using Google.Cloud.Translation.V2;

namespace TranslationApiDemo
{
    class Program
    {
        static void Main(string[] args)
        {
            var client = TranslationClient.Create();
            foreach (var language in client.ListLanguages(LanguageCodes.English))
            {
                Console.WriteLine($"{language.Code}\t{language.Name}");
            }
        }
    }
}

Take a minute or two to study the code*.* Note that we are listing the language names in English but it can be listed in any language.

Back in Cloud Shell, run the app. You should see the following output:

dotnet run

af        Afrikaans
sq        Albanian
am        Amharic
ar        Arabic
hy        Armenian
az        Azerbaijani
eu        Basque
be        Belarusian
...
yi        Yiddish
yo        Yoruba
zu        Zulu

Note: If this C# code does not work for you, verify the instructions you performed during Authenticate API requests step.

Using the following command to verify the value of GOOGLE_APPLICATION_CREDENTIALS environment variable:

echo GOOGLE_APPLICATION_CREDENTIALS

It should output the value "~/key.json".

If it does, next check that a service account was created and is located at "~/key.json" by using:

cat "~/key.json"

You should see something similar to:

{

"type": "service_account",

"project_id": "PROJECT_ID",

"private_key_id": "ff31939192529e07f42e4535fb20bb029def1276",

"Private_key":...

If you don't, revisit the Authenticate API requests step.

Summary

In this step, you were able to list all available languages in Translation API. You can find the complete list of supported languages on the Language Support page.

6. Translate text

You can use Translate API to translate a text in one language into another language. Text is translated using the Neural Machine Translation (NMT) model. If the NMT model is not supported for the requested language translation pair, then the Phrase-Based Machine Translation (PBMT) model is used.

To translate text, navigate to the Program.cs file inside the TranslationApiDemo folder and replace the code with the following:

using System;
using Google.Cloud.Translation.V2;

namespace TranslationApiDemo
{
    class Program
    {
        static void Main(string[] args)
        {
            var client = TranslationClient.Create();
            var text = "Hello World!";
            var response = client.TranslateText(text, LanguageCodes.Turkish, LanguageCodes.English);
            Console.WriteLine(response.TranslatedText);
        }
    }
}

Take a minute or two to study the code. It translates the text "Hello World" from English to Turkish*.*

Back in Cloud Shell, run the app. You should see the following output:

dotnet run

Selam Dünya!

Summary

In this step, you were able to use Translation API to translate a text from English to Turkish. Read more about Translating text.

7. Detect language

You can use Translate API to also detect the language of a text string.

To detect language, navigate to the Program.cs file inside the TranslationApiDemo folder and replace the code with the following:

using System;
using Google.Cloud.Translation.V2;

namespace TranslationApiDemo
{
    class Program
    {
        static void Main(string[] args)
        {
            var client = TranslationClient.Create();
            var text = "Selam Dünya!";
            var detection = client.DetectLanguage(text);
            Console.WriteLine($"Language: {detection.Language}\tConfidence: {detection.Confidence}");
        }
    }
}

Take a minute or two to study the code. It detects the language of the text "Selam Dünya!" which happens to be a Turkish phrase*.*

Back in Cloud Shell, run the app. You should see the following output:

dotnet run

Language: tr        Confidence: 1

Summary

In this step, you were able to detect the language of a piece of text using Translation API. Read more about Detecting language.

8. Congratulations!

You learned how to use the Translation API using C#!

Clean up

To avoid incurring charges to your Google Cloud Platform account for the resources used in this quickstart:

• Go to the Cloud Platform Console.
• Select the project you want to shut down, then click ‘Delete' at the top: this schedules the project for deletion.

Learn More

• Google Cloud Translation API: https://cloud.google.com/translate/docs
• C#/.NET on Google Cloud Platform: https://cloud.google.com/dotnet/
• Google Cloud .NET client: https://googlecloudplatform.github.io/google-cloud-dotnet/

License

This work is licensed under a Creative Commons Attribution 2.0 Generic License.