MVC4 Web API后参数为空

Question

Web API Post parameters are always Null

ASP.NET Web API POST parameter is null

What worked for these folks, doesn't seem to be working for me. I have almost exactly the same setup but still getting null in my second controller. The first one works just fine, but I can't replicate it in a second controller.

API Call

$.ajax
({
    type: "POST",
    url: "http://localhost:52441/api/login",
    data: { "Username": "test", "Password": "ptest" }
})
.done(function (data) {
    //var json = $.parseJSON(data);
    console.log(data);
});

Controller class

public class LoginController : ApiController
{
    public bool Post([FromBody]Creds creds)
    {
        return false;
    }
}

Creds class

public class Creds
{
    public string Username { get; set; }
    public string Password { get; set; }

    public Creds(string user, string pass)
    {
        this.Username = user;
        this.Password = pass;
    }
}

Like I said, this works inside of another controller (UsersController). When I pass { "First_Name": "John", "Last_Name": "Doe" } I properly receive a User object in the Post method public void Post([FromBody]User user)

What am I missing here?

Answer 1

Try with the modified code below:

API Call:

$.ajax
({
    type: "POST",
    url: "http://localhost:52441/api/login/validate",
    data: { "Username": "test", "Password": "ptest" }
})
.done(function (data) {
    //var json = $.parseJSON(data);
    console.log(data);
});

Controller class:

public class LoginController : ApiController
{
    [HttpPost]
    public bool Validate(Creds creds)
    {
        return false;
    }
}

Creds class:

Unchanged.

Answer 2

Follow the below Code

Web API Controller class

   public class LoginController : ApiController
        {
            public bool Validate([FromUri]Creds creds)
            {
                return false;
            }
        }

Creds class

public class Creds
{
    public string Username { get; set; }
    public string Password { get; set; }

    public Creds(string user, string pass)
    {
        this.Username = user;
        this.Password = pass;
    }
}

Either Use API Ajax call in the following manner

var RequestZipCode = { Username: "test", Password: "ptest" };
            $.ajax({
                type: "GET",
                data: Creds,
                url: "api/Name of the Controller/",
                contentType: "application/json",
                success: function (data){
                    ShowData(data);
            }
            });

Create a client application that will call webapi in the following manner

StringBuilder sbAPIRequest = new StringBuilder();
 sbAPIRequest.Append("?Username=test");
                sbAPIRequest.Append("&Password=ptest");

                HttpWebRequest httpWReq = (HttpWebRequest)WebRequest.Create(sbAPIRequest.ToString());

                httpWReq.Method = "GET";
                httpWReq.ContentType = "application/json;charset=UTF-8";
                httpWReq.ContentLength = 0;

                HttpWebResponse Httpresponse = (HttpWebResponse)httpWReq.GetResponse();
                string responseString = new StreamReader(Httpresponse.GetResponseStream()).ReadToEnd();

Answer 3

@StephenMuecke had the correct answer for me. It was because my class had a parameterless constructor.

I needed to do this to my Creds class

public class Creds
{
    public string Username { get; set; }
    public string Password { get; set; }

    public Creds()
    {
        this.Username = string.Empty;
        this.Password = string.Empty;
    }

    public Creds(string user, string pass)
    {
        this.Username = user;
        this.Password = pass;
    }
}

Big thank you to @StephenMuecke

Answer 4

You don't have to create a model to take multi post parameters. You can use dynamic object instead.

[HttpPost]
public SomeObject GetSomeObject([FromBody] dynamic postData) {
    var a = postData.[property name];
}