Web API 参数始终为空

Question

I have the following method in my Web API:

[AcceptVerbs("POST")]
public bool MoveFile([FromBody] FileUserModel model)
{
    if (model.domain == "abc")
    {
        return true;
    }
    return false;
}

The FileUserModel is defined as:

public class FileUserModel
{
    public string domain { get; set; }
    public string username { get; set; }
    public string password { get; set; }
    public string fileName { get; set; }
}

I'm trying to call this through Fiddler but whenever I do the model is always set to null. In Fiddler I've sent the composer to use POST , the url is there and correct as the debugger in Visual Studio breaks when called. The Request I've setup as:

User-Agent: Fiddler 
Host: localhost:46992 
Content-Length: 127 
Content-Type: application/json

The Request Body as:

"{
  "domain": "dcas"
  "username": "sample string 2",
  "password": "sample string 3",
  "fileName": "sample string 4"
}"

But whenever I run the composer when the debugger hits the breakpoint it always shows model is null.

Answer 1

You're missing a , in the request that you're sending. Also, because of the enclosing double quotes, you're actually sending a JSON string, not a JSON object. Removing the quotes and adding the comma should fix your problem.

{
    "domain": "dcas", // << here
    "username": "sample string 2",
    "password": "sample string 3",
    "fileName": "sample string 4"
}

Also, since you're posting a model, you don't need the [FromBody] attribute.

[AcceptVerbs("POST")]
public bool MoveFile(FileUserModel model)
{
    if (model.domain == "abc")
    {
        return true;
    }
    return false;
}

That should be just fine. For more information on this, see this blog .

Answer 2

You need to make ajax call like below

$(function () {
    var FileUserModel =    { domain: "dcas", username: "sample string 2", 
            password: "sample string 3", fileName: "sample string 4"};
    $.ajax({
        type: "POST",
        data :JSON.stringify(FileUserModel ),
        url: "api/MoveFile",
        contentType: "application/json"
    });
});

Dont forget to mark content type as json and on server side api code

[HttpPost]
public bool MoveFile([FromBody] FileUserModel model)
{
    if (model.domain == "abc")
    {
        return true;
    }
    return false;
}

Sending HTML Form Data in ASP.NET Web API

Answer 3

The problem you have is you are posting the JSON data with surrounding double quotes. Remove them and it should work.

Also fix the missing comma:

{
  "domain": "dcas",
  "username": "sample string 2",
  "password": "sample string 3",
  "fileName": "sample string 4"
}