如何将相同 url 的 PUT 和 DELETE 请求路由到不同的控制器方法

Question

我正在寻找这个问题的答案，发现this question，确实非常相似。但是，那里发布的解决方案似乎对我不起作用......我想知道这是否与问题的年龄有关。

给定以下网址：

/my/items/6

我希望此 URL 的 HTTP PUT 请求由一种操作方法处理，而 HTTP DELETE 请求由另一种操作方法处理。下面是我定义的路线（注意这些路线是基于一个区域，所以context 是一个AreaRegistrationContext 实例，如果这很重要的话）：

context.MapRoute(null,
    "my/items/{id}",
    new { area = "AreaName", controller = "ControllerName", action = "Replace" },
    new
    {
        httpMethod = new HttpMethodConstraint("POST", "PUT"),
    }
);

context.MapRoute(null,
    "my/items/{id}",
    new { area = "AreaName", controller = "ControllerName", action = "Destroy" },
    new
    {
        httpMethod = new HttpMethodConstraint("POST", "DELETE"),
    }
);

URL 生成适用于这两种路由，但是在路由传入请求时会出现问题。只有第一个声明的路由正确映射到其各自的操作。

我挖掘了HttpMethodConstraint源代码，发现它不关心"X-HTTP-Method-Override"参数，只关心HttpContext.Request.HttpMethod。

我能够使用以下自定义路由约束类解决此问题：

public class HttpMethodOverrideConstraint : HttpMethodConstraint
{
    public HttpMethodOverrideConstraint(params string[] allowedMethods) 
        : base(allowedMethods) { }

    protected override bool Match(HttpContextBase httpContext, Route route, 
        string parameterName, RouteValueDictionary values, 
        RouteDirection routeDirection)
    {
        var methodOverride = httpContext.Request
            .Unvalidated().Form["X-HTTP-Method-Override"];

        if (methodOverride == null)
            return base.Match(httpContext, route, parameterName, 
                values, routeDirection);

        return 
            AllowedMethods.Any(m => 
                string.Equals(m, httpContext.Request.HttpMethod, 
                    StringComparison.OrdinalIgnoreCase))
            &&
            AllowedMethods.Any(m => 
                string.Equals(m, methodOverride, 
                    StringComparison.OrdinalIgnoreCase))
        ;
    }
}

...以及这些路由定义：

context.MapRoute(null,
    "my/items/{id}",
    new { area = "AreaName", controller = "ControllerName", action = "Replace" },
    new
    {
        httpMethod = new HttpMethodOverrideConstraint("POST", "PUT"),
    }
);

context.MapRoute(null,
    "my/items/{id}",
    new { area = "AreaName", controller = "ControllerName", action = "Destroy" },
    new
    {
        httpMethod = new HttpMethodOverrideConstraint("POST", "DELETE"),
    }
);

我的问题：是否真的需要自定义路由约束来完成此任务？ 或者有什么方法可以使其与标准 MVC 和路由类一起开箱即用？

Answer 1

动作过滤器是你的朋友...

HttpDeleteAttribute、HttpPutAttribute、HttpPostAttribute、HttpGetAttribute