I have two actions

        [HttpPost("MyFromForm")]
        public async Task<IActionResult> MyFromForm([FromForm] RequestExample request)
        {
            return new OkObjectResult(request);
        }

        [HttpPost("MyFromBody")]
        public async Task<IActionResult> MyFromBody([FromBody] RequestExample request)
        {
            return new OkObjectResult(request);
        }

The class contains only one property of Dictionary type

    public class RequestExample
    {
        public Dictionary<string, string> DeviceDetails { get; set; }
    }

Request In case I send the data using swagger to these methods, The method having FromBody is working but the method having FromForm is not working .

1. Using: FromBody, I am able to receive the dictionary in the request.

{
  "deviceDetails": {
    "additionalProp1": "string",
    "additionalProp2": "string",
    "additionalProp3": "string"
  }
}

Curl Request:

curl -X POST "http://localhost:7002/MyItems/MyFromBody" -H  "accept: */*" -H  "Content-Type: application/json" -d "{\"deviceDetails\":{\"additionalProp1\":\"string\",\"additionalProp2\":\"string\",\"additionalProp3\":\"string\"}}" 

On the server-side, we are able to receive the data in the dictionary object.

2. Using: FromForm, I am not able to receive the dictionary in the request

Curl Request :

curl -X POST "http://localhost:7002/Abc/MyFromForm" -H  "accept: */*" -H  "Content-Type: multipart/form-data" -F "DeviceDetails={
      "additionalProp1": "string",
      "additionalProp2": "string",
      "additionalProp3": "string"
    }"

The output is empty.

Question: Why I am not able to receive the object in FromForm type of request?

CodePudding user response：

Seems you didn't change the Request body type. The FromForm attribute is for incoming data from a submitted form sent by the content-type application/x-www-form-urlencoded while the FromBody will parse the model the default way, which in most cases are sent by the content-type application/json, from the request body.

CodePudding user response：

You are not sending valid X FORM URL ENCODED data:

And example is this:

curl -d "additionalProp1=nice&additionalProp2=woohoo" -H "Content-Type: application/x-www-form-urlencoded" -X POST http://localhost:7002/Abc/MyFromForm

you are trying to send a json string as a form dictionary.

Form enconded values should be separated by ampersands without quotes on the keys or values.

Also using multipart/form-data is not to send form data, at least not generally speaking. multipart/form-data is used to upload files or binary data not text fields.

You should use -d instead of -F and Content-Type: application/x-www-form-urlencoded instead of multipart/form-data