Angular：调用帖子时出现错误的请求错误

Question

Using Angular 6 & C# here.

On the button click event of my form I want to save the data. The event calls an API which saves the data.

Below is my button click event:

submitData() {

      //After getting form values I create an object as below
      let myData = 
      {
        "name":name,
        "date": date,
        "status": status,
        "selection":selection,
        "createdBy": createdBy
      };

   this.myService.save(myData)
    .subscribe(
     (jsonData) => {
        //redirect etc after save

     });  
 }

In my above event selection itself holds array of objects as:

  0: {name: "u1", id: "123", type:"dev", comment: "comment1"}
  1: {name: "u2", id: "456", type:"prd", comment: "comment2"}

Also below is my service call:

   saveExtract(data) {
    return this.httpClient.post<any>(this.url + '/Save', data)
  .pipe(
    catchError())
);

}

Finally below is my c# api;

 [HttpPost("Save", Name = "Save")]
    public async Task Save([FromBody] SaveModel data)
    {
       //do save here etc
    }

But above code returns me 400 (Bad Request) error.

I even try to put the breakpoint in my api but its never hit.

So looks like something is wrong while I call my post.

Can Anyone point out the issue?

Thanks

---Updated---

So I was missed out the code to pass httpOptions and using Json.stringify. After passing it partially works as below:

const httpOptions = {
      headers: new HttpHeaders({
      'Content-Type': 'application/json'       
      })
    };

 saveExtract(data) {
    return this.httpClient.post<any>(this.url + '/Save', data, httpOptions)
  .pipe(
    catchError())
);

 this.myService.save(JSON.stringify(myData))
.subscribe(
 (jsonData) => {
    //redirect etc after save

 });

The above code works when I comment out the selection array which is a part of my data to be passed to the API. But does not work and gives bad request error when I pass selection array.

So can anyone point how can I pass array of object to it.

Answer 1

Here is a working demo with sending array to .net core, check the differences from your code.

Client Angular

export class FetchDataComponent {
constructor(http: HttpClient, @Inject('BASE_URL') baseUrl: string) {

    let selection = [{ "name": "n1", "id": 1 }, { "name": "n2", "id": 2 }, { "name": "n3", "id": 3 }];
    let myData =
    {
    "name": "Tom",
    "selection": selection,
    };
    http.post<any>(baseUrl + 'api/SampleData/Save', myData).subscribe(result => {

    });
}
}

Serser side.

[Route("api/[controller]")]
public class SampleDataController : Controller
{       
    [HttpPost("Save", Name = "Save")]
    public async Task Save([FromBody] SaveModel data)
    {
        //do save here etc
    }       
}

public class SaveModel
{
    public string Name { get; set; }
    public List<MySelection> Selection { get; set; }
}
public class MySelection
{
    public int Id { get; set; }
    public string Name { get; set; }
}

One More Node, you could add code below in Startup.cs to avoid api model validation filter.

services.AddMvc()
    .SetCompatibilityVersion(CompatibilityVersion.Version_2_2)
    .ConfigureApiBehaviorOptions(options =>
    {
        options.SuppressModelStateInvalidFilter = true;
    });