How to validate a VAT number using C# in .NET Framework

Let’s take a look at how to quickly and easily look up and validate VAT numbers within .NET Framework. It’s a lot easier than you might think. Let’s get started.

First, install Cloudmersive’s Validate API using the Package Manager console:

Install-Package Cloudmersive.APIClient.NET.Validate -Version 1.2.7

Then call VatVatLookup and input your VAT code.

using System;
using System.Diagnostics;
using Cloudmersive.APIClient.NET.Validate.Api;
using Cloudmersive.APIClient.NET.Validate.Client;
using Cloudmersive.APIClient.NET.Validate.Model;
namespace Example
{
    public class VatVatLookupExample
    {
        public void main()
        {
            // Configure API key authorization: Apikey
            Configuration.Default.AddApiKey("Apikey", "YOUR_API_KEY");
            // Uncomment below to setup prefix (e.g. Bearer) for API key, if needed
            // Configuration.Default.AddApiKeyPrefix("Apikey", "Bearer");
var apiInstance = new VatApi();
            var input = new VatLookupRequest(); // VatLookupRequest | Input VAT code
try
            {
                // Lookup a VAT code
                VatLookupResponse result = apiInstance.VatVatLookup(input);
                Debug.WriteLine(result);
            }
            catch (Exception e)
            {
                Debug.Print("Exception when calling VatApi.VatVatLookup: " + e.Message );
            }
        }
    }
}

That’s it! Your return will include whether the number is valid, as well as the business name, address, and country code.