从 DNX 迁移到 ASP.NET Core 2.0 时缺少/更改 API

Question

我一直致力于将应用程序从过时的 DNX 迁移到 ASP.NET Core 2.0。在这样做的同时，它发现命名空间和 API 几乎没有变化，例如 Microsoft.AspNet 到 Microsoft.AspNetCore。虽然我已经能够找到并修复大部分更改，但以下一项对我来说是个问题：

在继承自Route 的类中，在RouteAsync(RouteContext context) 方法中，使用DNX 时它是context.IsHandled = true;，我如何表示现在已经使用ASP.NET Core 2.0 处理了这个问题？

我试图从 GitHub 中查找更改历史记录，但似乎没有与此相关的内容。

Answer 1

不再需要从RouteAsync 调用context.IsHandled。如果您return 没有Task，则框架知道跳到下一条路线。如果您返回一个任务，那么框架将处理（处理）它。

旧 DNX / MVC6 / 预览代码

public async Task RouteAsync(RouteContext context)
{
    var requestPath = context.HttpContext.Request.Path.Value;

    if (!string.IsNullOrEmpty(requestPath) && requestPath[0] == '/')
    {
        // Trim the leading slash
        requestPath = requestPath.Substring(1);
    }

    // Get the page id that matches.
    TPrimaryKey id;

    //If this returns false, that means the URI did not match
    if (!GetPageList().TryGetValue(requestPath, out id))
    {
        return;
    }

    //Invoke MVC controller/action
    var oldRouteData = context.RouteData;
    var newRouteData = new RouteData(oldRouteData);
    newRouteData.Routers.Add(_target);

    newRouteData.Values["controller"] = _controller;
    newRouteData.Values["action"] = _action;

    // This will be the primary key of the database row.
    // It might be an integer or a GUID.
    newRouteData.Values["id"] = id;

    try
    {
        context.RouteData = newRouteData;
        await _target.RouteAsync(context);
    }
    finally
    {
        // Restore the original values to prevent polluting the route data.
        if (!context.IsHandled)
        {
            context.RouteData = oldRouteData;
        }
    }
}

新的 .NET Core 1.x / .NET Core 2.x 代码

public async Task RouteAsync(RouteContext context)
{
    var requestPath = context.HttpContext.Request.Path.Value;

    if (!string.IsNullOrEmpty(requestPath) && requestPath[0] == '/')
    {
        // Trim the leading slash
        requestPath = requestPath.Substring(1);
    }

    // Get the page id that matches.
    TPrimaryKey id;

    //If this returns false, that means the URI did not match
    if (!GetPageList().TryGetValue(requestPath, out id))
    {
        return;
    }

    //Invoke MVC controller/action
    var routeData = context.RouteData;

    routeData.Values["controller"] = _controller;
    routeData.Values["action"] = _action;

    // This will be the primary key of the database row.
    // It might be an integer or a GUID.
    routeData.Values["id"] = id;

    await _target.RouteAsync(context);
}

此处的完整代码（针对 .NET Core 1/2 更新）：Change route collection of MVC6 after startup