OnDelete Handler always trigger a bad request - ajax

Question

Trying to be more consistent with HTTP verbs, I'm trying to call a delete Handler on a Razor Page via AJAX;
Here's my AJAX code, followed by the C# code on my page :
return new Promise(function (resolve: any, reject: any) {
let ajaxConfig: JQuery.UrlAjaxSettings =
{
type: "DELETE",
url: url,
data: JSON.stringify(myData),
dataType: "json",
contentType: "application/json",
success: function (data) { resolve(data); },
error: function (data) { reject(data); }
};
$.ajax(ajaxConfig);
});
my handler on my cshtml page :
public IActionResult OnDeleteSupprimerEntite(int idEntite, string infoCmpl)
{
// my code
}
which never reaches ... getting a bad request instead !
When I switch to a 'GET' - both the type of the ajax request and the name of my handler function ( OnGetSupprimerEntite ) - it does work like a charm.
Any ideas ? Thanks !

Answer 1

Short answer: The 400 bad request indicates the request doesn't fulfill the server side's needs.
Firstly, your server is expecting a form by;
public IActionResult OnDeleteSupprimerEntite(int idEntite, string infoCmpl)
{
// my code
}
However, you're sending the payload in application/json format.
Secondly, when you sending a form data, don't forget to add a csrf token:
#inject Microsoft.AspNetCore.Antiforgery.IAntiforgery Xsrf
<script>
function deleteSupprimerEntite(myData){
var url = "Index?handler=SupprimerEntite";
return new Promise(function (resolve, reject) {
let ajaxConfig = {
type: "DELETE",
url: url,
data: myData ,
success: function (data) { resolve(data); },
error: function (data) { reject(data); }
};
$.ajax(ajaxConfig);
})
}
document.querySelector("#testbtn").addEventListener("click",function(e){
var myData ={
idEntite:1,
infoCmpl:"abc",
__RequestVerificationToken: "#(Xsrf.GetAndStoreTokens(HttpContext).RequestToken)",
};
deleteSupprimerEntite(myData);
});
</script>
A Working Demo:
Finally, in case you want to send in json format, you could change the server side Handler to:
public class MyModel {
public int idEntite {get;set;}
public string infoCmpl{get;set;}
}
public IActionResult OnDeleteSupprimerEntite([FromBody]MyModel xmodel)
{
return new JsonResult(xmodel);
}
And the js code should be :
function deleteSupprimerEntiteInJson(myData){
var url = "Index?handler=SupprimerEntite";
return new Promise(function (resolve, reject) {
let ajaxConfig = {
type: "DELETE",
url: url,
data: JSON.stringify(myData) ,
contentType:"application/json",
headers:{
"RequestVerificationToken": "#(Xsrf.GetAndStoreTokens(HttpContext).RequestToken)",
},
success: function (data) { resolve(data); },
error: function (data) { reject(data); }
};
$.ajax(ajaxConfig);
})
}
document.querySelector("#testbtn").addEventListener("click",function(e){
var myData ={
idEntite:1,
infoCmpl:"abc",
};
deleteSupprimerEntiteInJson(myData);
});