.NET SDK

Official C# SDK for the Truelist email validation API. Supports .NET 6.0+, .NET 8.0+, and .NET Standard 2.1.

Installation

dotnet add package Truelist

No external dependencies.

Quick start

using Truelist;

var client = new TruelistClient("your-api-key");
var result = await client.ValidateAsync("user@example.com");

if (result.IsValid)
    Console.WriteLine("Email is valid!");

Configuration

var client = new TruelistClient("your-api-key", new TruelistOptions
{
    BaseUrl = "https://api.truelist.io",
    Timeout = TimeSpan.FromSeconds(10),
    MaxRetries = 2,
});

Result properties

result.Email;        // "user@example.com"
result.Domain;       // "example.com"
result.State;        // "ok", "email_invalid", "accept_all", "unknown"
result.SubState;     // "email_ok", "is_disposable", "is_role", ...
result.Suggestion;   // null or correction
result.IsValid;      // true
result.IsDisposable; // false
result.IsRole;       // false

Dependency injection

builder.Services.AddTruelist("your-api-key");

// Then inject:
public class EmailService(TruelistClient truelist)
{
    public async Task<bool> IsEmailValidAsync(string email) =>
        (await truelist.ValidateAsync(email)).IsValid;
}

CancellationToken support

using var cts = new CancellationTokenSource(TimeSpan.FromSeconds(5));
var result = await client.ValidateAsync("user@example.com", cts.Token);

Error handling

using Truelist.Exceptions;

try
{
    var result = await client.ValidateAsync("user@example.com");
}
catch (AuthenticationException) { /* 401 — never retried */ }
catch (RateLimitException ex) { Console.WriteLine(ex.RetryAfterSeconds); }
catch (ApiException ex) { Console.WriteLine($"{ex.StatusCode}: {ex.ResponseBody}"); }

Package link