# ASP.NET Core (/pt-BR/quickstarts/aspnet-core)

<!-- agent-signals: reading_time_min: 4 · est_tokens: 2564 · updated: 2026-07-30 -->
Related: [Node.js](/pt-BR/quickstarts/nodejs.md), [Next.js](/pt-BR/quickstarts/nextjs.md), [Express](/pt-BR/quickstarts/express.md), [NestJS](/pt-BR/quickstarts/nestjs.md), [Fastify](/pt-BR/quickstarts/fastify.md), [Hono](/pt-BR/quickstarts/hono.md)

<div id="prerequisites">
  ## Pré-requisitos [#pré-requisitos]
</div>

* .NET 6.0+
* Uma chave de API do Firecrawl — [obtenha uma gratuitamente](https://www.firecrawl.dev/app/api-keys)

<div id="configuration">
  ## Configuração [#configuração]
</div>

Adicione sua chave de API ao `appsettings.json`:

```json
{
  "Firecrawl": {
    "ApiKey": "fc-YOUR-API-KEY",
    "BaseUrl": "https://api.firecrawl.dev/v2"
  }
}
```

Ou use variáveis de ambiente / segredos do usuário:

```bash
export Firecrawl__ApiKey=fc-YOUR-API-KEY
```

<div id="create-a-service">
  ## Criar um serviço [#criar-um-serviço]
</div>

Crie `Services/FirecrawlService.cs`:

```csharp
using System.Net.Http.Headers;
using System.Text;
using System.Text.Json;

public class FirecrawlService
{
    private readonly HttpClient _http;
    private readonly string _baseUrl;

    public FirecrawlService(IConfiguration config)
    {
        _baseUrl = config["Firecrawl:BaseUrl"] ?? "https://api.firecrawl.dev/v2";
        _http = new HttpClient();
        _http.DefaultRequestHeaders.Authorization =
            new AuthenticationHeaderValue("Bearer", config["Firecrawl:ApiKey"]);
    }

    public async Task<JsonDocument> SearchAsync(string query, int limit = 5)
    {
        var content = new StringContent(
            JsonSerializer.Serialize(new { query, limit }),
            Encoding.UTF8, "application/json");

        var response = await _http.PostAsync($"{_baseUrl}/search", content);
        response.EnsureSuccessStatusCode();
        return JsonDocument.Parse(await response.Content.ReadAsStringAsync());
    }

    public async Task<JsonDocument> ScrapeAsync(string url)
    {
        var content = new StringContent(
            JsonSerializer.Serialize(new { url }),
            Encoding.UTF8, "application/json");

        var response = await _http.PostAsync($"{_baseUrl}/scrape", content);
        response.EnsureSuccessStatusCode();
        return JsonDocument.Parse(await response.Content.ReadAsStringAsync());
    }

    public async Task<JsonDocument> InteractAsync(string url, string prompt, string? followUp = null)
    {
        // 1. Fazer scraping para abrir uma sessão de navegador
        var scrapeContent = new StringContent(
            JsonSerializer.Serialize(new { url, formats = new[] { "markdown" } }),
            Encoding.UTF8, "application/json");

        var scrapeRes = await _http.PostAsync($"{_baseUrl}/scrape", scrapeContent);
        scrapeRes.EnsureSuccessStatusCode();
        var scrapeDoc = JsonDocument.Parse(await scrapeRes.Content.ReadAsStringAsync());
        var scrapeId = scrapeDoc.RootElement
            .GetProperty("data").GetProperty("metadata").GetProperty("scrapeId").GetString();

        // 2. Enviar o primeiro prompt
        var firstPrompt = new StringContent(
            JsonSerializer.Serialize(new { prompt }),
            Encoding.UTF8, "application/json");
        await _http.PostAsync($"{_baseUrl}/scrape/{scrapeId}/interact", firstPrompt);

        // 3. Enviar o prompt de acompanhamento
        JsonDocument? result = null;
        if (followUp != null)
        {
            var followUpContent = new StringContent(
                JsonSerializer.Serialize(new { prompt = followUp }),
                Encoding.UTF8, "application/json");
            var followUpRes = await _http.PostAsync(
                $"{_baseUrl}/scrape/{scrapeId}/interact", followUpContent);
            followUpRes.EnsureSuccessStatusCode();
            result = JsonDocument.Parse(await followUpRes.Content.ReadAsStringAsync());
        }

        // 4. Encerrar a sessão
        await _http.DeleteAsync($"{_baseUrl}/scrape/{scrapeId}/interact");

        return result ?? scrapeDoc;
    }
}
```

<div id="register-and-use">
  ## Registre e use [#registre-e-use]
</div>

Em `Program.cs`:

```csharp
var builder = WebApplication.CreateBuilder(args);
builder.Services.AddSingleton<FirecrawlService>();

var app = builder.Build();

app.MapPost("/api/search", async (FirecrawlService firecrawl, SearchRequest req) =>
{
    var result = await firecrawl.SearchAsync(req.Query, req.Limit);
    return Results.Ok(result.RootElement);
});

app.MapPost("/api/scrape", async (FirecrawlService firecrawl, ScrapeRequest req) =>
{
    var result = await firecrawl.ScrapeAsync(req.Url);
    return Results.Ok(result.RootElement);
});

app.MapPost("/api/interact", async (FirecrawlService firecrawl, InteractRequest req) =>
{
    var result = await firecrawl.InteractAsync(req.Url, req.Prompt, req.FollowUp);
    return Results.Ok(result.RootElement);
});

app.Run();

record SearchRequest(string Query, int Limit = 5);
record ScrapeRequest(string Url);
record InteractRequest(string Url, string Prompt, string? FollowUp = null);
```

<div id="run-it">
  ## Execute [#execute]
</div>

```bash
dotnet run
```

<div id="test-it">
  ## Experimente [#experimente]
</div>

```bash
# Fazer uma busca na web
curl -X POST http://localhost:5000/api/search \
  -H "Content-Type: application/json" \
  -d '{"query": "firecrawl web scraping"}'

# Fazer scraping de uma página
curl -X POST http://localhost:5000/api/scrape \
  -H "Content-Type: application/json" \
  -d '{"url": "https://example.com"}'

# Interagir com uma página
curl -X POST http://localhost:5000/api/interact \
  -H "Content-Type: application/json" \
  -d '{"url": "https://www.amazon.com", "prompt": "Search for iPhone 16 Pro Max", "followUp": "Click on the first result and tell me the price"}'
```

<div id="next-steps">
  ## Próximos passos [#próximos-passos]
</div>

<CardGroup cols="2">
  <Card title="Documentação de busca" icon="<svg xmlns=&#x22;http://www.w3.org/2000/svg&#x22; viewBox=&#x22;0 0 24 24&#x22; fill=&#x22;none&#x22;><path d=&#x22;M8 7L16 7&#x22; stroke=&#x22;currentColor&#x22; stroke-linecap=&#x22;round&#x22; stroke-linejoin=&#x22;round&#x22; stroke-width=&#x22;1.5&#x22;/><path d=&#x22;M8 11L12 11&#x22; stroke=&#x22;currentColor&#x22; stroke-linecap=&#x22;round&#x22; stroke-linejoin=&#x22;round&#x22; stroke-width=&#x22;1.5&#x22;/><path d=&#x22;M13 21.5V21C13 18.1716 13 16.7574 13.8787 15.8787C14.7574 15 16.1716 15 19 15H19.5M20 13.3431V10C20 6.22876 20 4.34315 18.8284 3.17157C17.6569 2 15.7712 2 12 2C8.22877 2 6.34315 2 5.17157 3.17157C4 4.34314 4 6.22876 4 10L4 14.5442C4 17.7892 4 19.4117 4.88607 20.5107C5.06508 20.7327 5.26731 20.9349 5.48933 21.1139C6.58831 22 8.21082 22 11.4558 22C12.1614 22 12.5141 22 12.8372 21.886C12.9044 21.8623 12.9702 21.835 13.0345 21.8043C13.3436 21.6564 13.593 21.407 14.0919 20.9081L18.8284 16.1716C19.4065 15.5935 19.6955 15.3045 19.8478 14.9369C20 14.5694 20 14.1606 20 13.3431Z&#x22; stroke=&#x22;currentColor&#x22; stroke-linecap=&#x22;round&#x22; stroke-linejoin=&#x22;round&#x22; stroke-width=&#x22;1.5&#x22;/></svg>" href="/pt-BR/features/search">
    Faça uma busca na web e obtenha o conteúdo completo da página
  </Card>

  <Card title="Documentação de scraping" icon="<svg xmlns=&#x22;http://www.w3.org/2000/svg&#x22; viewBox=&#x22;0 0 24 24&#x22; fill=&#x22;none&#x22;><path d=&#x22;M8 7L16 7&#x22; stroke=&#x22;currentColor&#x22; stroke-linecap=&#x22;round&#x22; stroke-linejoin=&#x22;round&#x22; stroke-width=&#x22;1.5&#x22;/><path d=&#x22;M8 11L12 11&#x22; stroke=&#x22;currentColor&#x22; stroke-linecap=&#x22;round&#x22; stroke-linejoin=&#x22;round&#x22; stroke-width=&#x22;1.5&#x22;/><path d=&#x22;M13 21.5V21C13 18.1716 13 16.7574 13.8787 15.8787C14.7574 15 16.1716 15 19 15H19.5M20 13.3431V10C20 6.22876 20 4.34315 18.8284 3.17157C17.6569 2 15.7712 2 12 2C8.22877 2 6.34315 2 5.17157 3.17157C4 4.34314 4 6.22876 4 10L4 14.5442C4 17.7892 4 19.4117 4.88607 20.5107C5.06508 20.7327 5.26731 20.9349 5.48933 21.1139C6.58831 22 8.21082 22 11.4558 22C12.1614 22 12.5141 22 12.8372 21.886C12.9044 21.8623 12.9702 21.835 13.0345 21.8043C13.3436 21.6564 13.593 21.407 14.0919 20.9081L18.8284 16.1716C19.4065 15.5935 19.6955 15.3045 19.8478 14.9369C20 14.5694 20 14.1606 20 13.3431Z&#x22; stroke=&#x22;currentColor&#x22; stroke-linecap=&#x22;round&#x22; stroke-linejoin=&#x22;round&#x22; stroke-width=&#x22;1.5&#x22;/></svg>" href="/pt-BR/features/scrape">
    Todas as opções de scraping, incluindo formatos, ações e proxies
  </Card>

  <Card title="Documentação de interagir" icon="<svg xmlns=&#x22;http://www.w3.org/2000/svg&#x22; viewBox=&#x22;0 0 24 24&#x22; fill=&#x22;none&#x22;><path d=&#x22;M8 7L16 7&#x22; stroke=&#x22;currentColor&#x22; stroke-linecap=&#x22;round&#x22; stroke-linejoin=&#x22;round&#x22; stroke-width=&#x22;1.5&#x22;/><path d=&#x22;M8 11L12 11&#x22; stroke=&#x22;currentColor&#x22; stroke-linecap=&#x22;round&#x22; stroke-linejoin=&#x22;round&#x22; stroke-width=&#x22;1.5&#x22;/><path d=&#x22;M13 21.5V21C13 18.1716 13 16.7574 13.8787 15.8787C14.7574 15 16.1716 15 19 15H19.5M20 13.3431V10C20 6.22876 20 4.34315 18.8284 3.17157C17.6569 2 15.7712 2 12 2C8.22877 2 6.34315 2 5.17157 3.17157C4 4.34314 4 6.22876 4 10L4 14.5442C4 17.7892 4 19.4117 4.88607 20.5107C5.06508 20.7327 5.26731 20.9349 5.48933 21.1139C6.58831 22 8.21082 22 11.4558 22C12.1614 22 12.5141 22 12.8372 21.886C12.9044 21.8623 12.9702 21.835 13.0345 21.8043C13.3436 21.6564 13.593 21.407 14.0919 20.9081L18.8284 16.1716C19.4065 15.5935 19.6955 15.3045 19.8478 14.9369C20 14.5694 20 14.1606 20 13.3431Z&#x22; stroke=&#x22;currentColor&#x22; stroke-linecap=&#x22;round&#x22; stroke-linejoin=&#x22;round&#x22; stroke-width=&#x22;1.5&#x22;/></svg>" href="/pt-BR/features/interact">
    Clique, preencha formulários e extraia conteúdo dinâmico
  </Card>

  <Card title="Referência da API" icon="<svg xmlns=&#x22;http://www.w3.org/2000/svg&#x22; viewBox=&#x22;0 0 24 24&#x22; fill=&#x22;none&#x22;><path d=&#x22;M16 6.99998L19.0664 9.64296C20.3554 10.7541 21 11.3096 21 12C21 12.6903 20.3555 13.2459 19.0664 14.357L16 17&#x22; stroke=&#x22;currentColor&#x22; stroke-linecap=&#x22;round&#x22; stroke-linejoin=&#x22;round&#x22; stroke-width=&#x22;1.5&#x22;/><path d=&#x22;M8 6.99998L4.93365 9.64296C3.64455 10.7541 3 11.3096 3 12C3 12.6903 3.64455 13.2459 4.93365 14.357L8 17&#x22; stroke=&#x22;currentColor&#x22; stroke-linecap=&#x22;round&#x22; stroke-linejoin=&#x22;round&#x22; stroke-width=&#x22;1.5&#x22;/></svg>" href="/pt-BR/api-reference/v2-introduction">
    Documentação completa da API REST
  </Card>
</CardGroup>
