### Configuration File Example

Source: https://github.com/zuoxiange/nuonuosdk/blob/main/README.md

Example JSON structure for appsettings.json to configure NuoNuoSdk.

```json
{
  "NuoNuo": {
    "AppKey": "your_app_key",
    "AppSecret": "your_app_secret",
    "UserTax": "your_user_tax",
    "AccessToken": "your_access_token",
    "Timeout": 30
  }
}
```

--------------------------------

### Usage Example - InvoiceController

Source: https://github.com/zuoxiange/nuonuosdk/blob/main/README.md

Example of using INuoNuoSdk within an ASP.NET Core controller to perform operations like getting merchant token, querying invoice stock, and requesting billing.

```csharp
public class InvoiceController : ControllerBase
{
    private readonly INuoNuoSdk _nuoNuoSdk;
    
    public InvoiceController(INuoNuoSdk nuoNuoSdk)
    {
        _nuoNuoSdk = nuoNuoSdk;
    }
    
    [HttpGet("token")]
    public async Task<IActionResult> GetToken()
    {
        // 获取访问令牌
        var token = await _nuoNuoSdk.GetMerchantTokenAsync();
        return Ok(token);
    }
    
    [HttpGet("stock")]
    public async Task<IActionResult> GetInvoiceStock()
    {
        // 查询发票余量
        var stockRes = await _nuoNuoSdk.GetInvoiceStockAsync(new GetInvoiceStockRequest
        {
            // AccessToken 会自动从配置中获取，也可以手动指定
        });
        return Ok(stockRes);
    }
    
    [HttpPost("billing")]
    public async Task<IActionResult> RequestBilling([FromBody] RequestBillingRequest request)
    {
        // 请求开具发票
        var result = await _nuoNuoSdk.RequestBillingRequest(request);
        return Ok(result);
    }
}
```

--------------------------------

### Install NuoNuoSdk

Source: https://github.com/zuoxiange/nuonuosdk/blob/main/README.md

Command to install the NuoNuoSdk package using the .NET CLI.

```bash
dotnet add package NuoNuoOpenSdk
```

--------------------------------

### Configure Services - From Configuration File

Source: https://github.com/zuoxiange/nuonuosdk/blob/main/README.md

Example of configuring NuoNuoSdk services by reading settings from a configuration file.

```csharp
// 方式一：从配置文件读取
builder.Services.AddNuoNuoSdk(builder.Configuration, "NuoNuo");
```

--------------------------------

### Configure Services - Direct Configuration

Source: https://github.com/zuoxiange/nuonuosdk/blob/main/README.md

Example of configuring NuoNuoSdk services by directly providing options.

```csharp
// 方式二：直接配置
builder.Services.AddNuoNuoSdk(options =>
{
    options.AppKey = "your_app_key";
    options.AppSecret = "your_app_secret";
    options.UserTax = "your_user_tax";
    options.AccessToken = "your_access_token"; // 可选
    options.Timeout = 30; // 超时时间（秒）
});
```

--------------------------------

### Advanced Usage - Error Handling

Source: https://github.com/zuoxiange/nuonuosdk/blob/main/README.md

Example demonstrating how to handle both business logic errors and network errors when using NuoNuoSdk.

```csharp
try
{
    var result = await _nuoNuoSdk.GetInvoiceStockAsync(request);
    if (result.Success)
    {
        // 处理成功结果
        Console.WriteLine($"库存查询成功: {result.Result}");
    }
    else
    {
        // 处理业务错误
        Console.WriteLine($"业务错误: {result.Code} - {result.Describe}");
    }
}
catch (HttpRequestException ex)
{
    // 处理网络错误
    Console.WriteLine($"网络错误: {ex.Message}");
}
```

--------------------------------

### Advanced Usage - Custom HTTP Client Configuration

Source: https://github.com/zuoxiange/nuonuosdk/blob/main/README.md

Example of customizing the HttpClient used by NuoNuoSdk, such as setting a custom timeout.

```csharp
builder.Services.AddNuoNuoSdk(builder.Configuration)
    .ConfigureHttpClient(client =>
    {
        client.Timeout = TimeSpan.FromSeconds(60);
        // 其他自定义配置
    });
```

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