Post FromBody Always Null

Question

I've got a new API that I'm building with ASP.NET Core, and I can't get any data POST'ed to an endpoint.

Here's what the endpoint looks like:

[HttpPost] [Route("StudentResults")] public async Task<IActionResult> GetStudentResults([FromBody]List<string> userSocs, [FromBody]int collegeId) {     var college = await _collegeService.GetCollegeByID(collegeId);     // var occupations = await _laborMarketService.GetOccupationProgramsBySocsAndCollege(userSocs, college);     return Ok(); } 

And here's what my payload that I'm sending through Postman looks like:

{     "userSocs": [             "291123",             "291171",             "312021",             "291071",             "152031",             "533011"         ],     "collegeId": 1 } 

I'm making sure that I have postman set as a POST, with Content-Type application/json. What am I doing wrong?

Answer 1

You get always null because you need to encapsulate all your post variables inside only one object. Like this:

public class MyPostModel {     public List<string> userSocs {get; set;}     public int collegeId {get; set;} } 

and then

public async Task<IActionResult> GetStudentResults([FromBody] MyPostModel postModel) 

Answer 2

If the model is null, check:

1) Where the data is sent: body, form? and based on that add the decorator to the action. For ex:

[HttpPost] public JsonResult SaveX([FromBody]MyVM vm) { ... } 

2) Check ModelState: if it's invalid the vm will not be bound so it will be null.

if (ModelState.IsValid) { ... }