如何在.net核心中调用带有参数的动作？

Posted 2023-04-13

【中文标题】如何在.net核心中调用带有参数的动作？

【英文标题】：How to call an action with parameters in .net core?

【发布时间】：2020-05-04 12:07:10

【问题描述】：

所以我在 Startup.cs 中设置了以下默认模式：

app.UseEndpoints(endpoints =>

    endpoints.MapControllerRoute(
        name: "default",
        pattern: "controller/action/id?");
);

这是我的控制器：

[ApiController]
[Route("[controller]")]
public class WeatherForecastController : ControllerBase

    private static readonly string[] Summaries = new[]
    
        "Freezing", "Bracing", "Chilly", "Cool", "Mild", "Warm", "Balmy", "Hot", "Sweltering", "Scorching"
    ;

    private readonly ILogger<WeatherForecastController> _logger;

    public WeatherForecastController(ILogger<WeatherForecastController> logger)
    
        _logger = logger;
    

    [HttpGet]
    [Route("[action]")]
    public IEnumerable<WeatherForecast> Get()
    
        var rng = new Random();
        return Enumerable.Range(1, 5).Select(index => new WeatherForecast
        
            Date = DateTime.Now.AddDays(index),
            TemperatureC = rng.Next(-20, 0),
            Summary = Summaries[rng.Next(Summaries.Length)]
        )
        .ToArray();
    

    [HttpGet]
    [Route("[action]")]
    public IEnumerable<WeatherForecast> Grab()
    
        var rng = new Random();
        return Enumerable.Range(1, 5).Select(index => new WeatherForecast
        
            Date = DateTime.Now.AddDays(index),
            TemperatureC = rng.Next(1, 55),
            Summary = Summaries[rng.Next(Summaries.Length)]
        )
        .ToArray();
    

    [Route("[action]")]
    [HttpGet("i:int")]
    public IEnumerable<WeatherForecast> Snatch(int i)
    
        var rng = new Random();
        return Enumerable.Range(i, 5).Select(index => new WeatherForecast
        
            Date = DateTime.Now.AddDays(index),
            TemperatureC = rng.Next(55, 100),
            Summary = Summaries[rng.Next(Summaries.Length)]
        )
        .ToArray();
    

现在，当我调用 https://localhost:44388/weatherforecast/grab 或 https://localhost:44388/weatherforecast/get 时，它可以正常工作，但如果我调用 https://localhost:44388/weatherforecast/Snatch/1，我会在浏览器中看到 Error: Cannot match any routes.。

我已经设置了最后一个方法 Snatch 与它期望一个 int 的参数，所以我做错了什么？

【参考方案1】：

您需要使用一个路由模板来获得所需的行为

//GET weatherforecast/Snatch/1
[Route("[action]/i:int")]
[HttpGet]
public IEnumerable<WeatherForecast> Snatch(int i) 
    //...

现在这是一个ApiController，所有操作只使用HttpVerb就足够了

在构建 REST API 时，您很少会希望在操作方法上使用 [Route(...)]，因为该操作将接受所有 HTTP 方法。最好使用更具体的 Http*Verb*Attributes 来准确了解您的 API 支持什么。 REST API 的客户端应该知道哪些路径和 HTTP 动词映射到特定的逻辑操作。

//GET weatherforecast/Snatch/1
[HttpGet("[action]/i:int")]
public IEnumerable<WeatherForecast> Snatch(int i) 
    //...

这可以通过聚合模板进一步简化

[ApiController]
[Route("[controller]/[action]")] //<-- NOTE THIS
public class WeatherForecastController : ControllerBase 

    //...

    //GET weatherforecast/get
    [HttpGet]
    public IEnumerable<WeatherForecast> Get() 
        //...
    

    //GET weatherforecast/grab
    [HttpGet]
    public IEnumerable<WeatherForecast> Grab() 
        //...
    

    //GET weatherforecast/Snatch/1
    [HttpGet("i:int")]
    public IEnumerable<WeatherForecast> Snatch(int i) 
        //...
    

参考Routing to controller actions in ASP.NET Core

参考Routing in ASP.NET Core

【讨论】：

谢谢，我确实找到了您链接的那些参考文献，但我想我误解了它们。所以现在我可以删除其他两种方法中的 Route 属性并安全地使用[HttpGet("[action]")] ?