asp.net core razor pages 支持delete和put请求

Question

Recently, I read about request handling in asp.net core razor pages and it says that it supports head requests using the convention:

public void OnHead()
{
}

It worked perfectly. And then I also tried delete using the same convention.

public void OnDelete()
{
}

But when I send a delete request using postman, it returns a bad request (500). I'm not sure if i need to provide additional configurations to use delete requests. Any one could help me pls.

Answer 1

Assuming you have a markup like this:

<button type="submit" asp-page-handler="delete" 
        asp-route-id="@contact.Id">delete</button>

The correct method for delete would be OnPostDelete (or OnPostDeleteAsync ).

So, could update to:

public void OnPostDelete(int id)
{
}

The docs state:

By convention, the name of the handler method is selected based on the value of the handler parameter according to the scheme OnPost[handler]Async

Further, the Async suffix is optional:

The Async naming suffix is optional but is often used by convention for asynchronous functions.

Answer 2

There is no OnDelete / OnPut . This is because Razor Pages are directly geared towards web views, ie pages displaying in a browser tab/window. There is no native way in a browser to send DELETE/PUT requests, so there's no reason to support them. Instead, such tasks are handled via an HTML form element, which would send via POST. As such, you would use OnPost() to handle it.

The docs recommend creating a new Razor Page for delete, with its own OnGet and OnPost methods, specifically geared to handling deletes. Alternatively, you may simply add an additional handler to an existing Razor Page in the form of OnPost[Something] . For a delete, that would likely be OnPostDelete , while for an update, you'd likely have OnPostUpdate . The name doesn't matter, except that you will need to pass it as a handler such as:

<form asp-page="Foo" asp-handler="Delete">

If you need to interact via a thin client ( HttpClient , AJAX, Postman, etc.), then you should avoid Razor Pages altogether and stick with traditional controllers, which fully supports all HTTP verbs.

Answer 3

This is an update for 2023.

You can easily utilize the DELETE verb of an Ajax request:

public async Task<IActionResult> OnDeleteAsync(int id)
{
    await _myService.DeleteUser(id);

    return new OkResult();
}

With jQuery it looks something like this:

<script>

$(".deletebtn").on("click", function (e) { 
    deleteUser($(this).data("id"));
});

const deleteUser = function (userId) {
    $.ajax({
        method: 'DELETE', // specify HTTP verb.
        url: '/account/users', // specify right path to your controller/razor page
        headers:
        {
            "RequestVerificationToken": "<get your token here>"
        },
        data: { id: userId },
        success: function () {
            window.location.href = "/account/users"; // reload page
        },
        error: function (response) {
            alert(response);
        }
    });
};

</script>
<button class="deletebtn" data-id="123">Delete</button>
<button class="deletebtn" data-id="456">Delete</button>
<button class="deletebtn" data-id="1111">Delete</button>

Similarly the HTTP verbs GET, POST, PUT can also be utilized:

OnGet(), OnPost(), OnPut()

and their async equivalents

OnGetAsync(), OnPostAsync(), OnPutAsync()

Usage eg:

OnGetUsersAsync() // GET a list of Users async. 
OnPostUserAsync() // POST (add) a User async. 
OnPutUpdateMyUserAsync() // PUT (update) a user async
OnDeleteCoffeCup(id)  /// DELETE method sync.

In addition you can add your own experimental HTTP verbs. See eg here https://khalidabuhakmeh.com/adding-experimental-http-methods-to-as.net-core