This article shows you how to send a message to a WhatsApp group in Microsoft’s .net language: C# using Visual Studio 2019.
If you are using Visual Studio 2022, please read this tutorial instead.
You MUST obtain the secret gateway number by signing up for a Forever Green account before you can send a message to a WhatsApp group. Instructions are available on the official site.
To send a WhatsApp group message in C#, do this:
- Create a new group with a unique name. The API won’t work if it’s not unique.
- Add the secret gateway to the group.
- Say “Hi” to the group to let the gateway recognize the new group.
- Copy the following source code to the main class in your Console Application in Visual Studio.
- Customize the TODO lines in the C# program:
- Specify your gateway instance ID on line 10.
- Specify your Client ID and Client secret on lines 10 and 11.
- Specify the group admin number (i.e. your WhatsApp number including the country code) on line 19.
- Specify the group name (e.g. Happy Club) on line 20.
- Specify the content of the message on line 21.
- Add the reference “System.Web.Extensions” by doing this:
- Right-click on your project node in the Solution Explorer panel.
- Choose “Add” -> “Reference…”
- Choose “Framework” on the left pane.
- Look for “System.Web.Extensions” in the middle pane. Check the checkbox in front of it.
- Click OK.
- Build and run the application in Visual Studio.
As mentioned at the beginning of this tutorial, you will need a trial account to call the above API. Go sign up now.
Happy coding :)