c# - Web API 2 POST 请求返回 null

Question

问题是，当进入方法时，“session”为空。如您所见， header 和​​ JSON 对象是正确的。你能告诉我我做错了什么吗？

我的带 Angular 的 POST 请求:

        $scope.send = function () {
        var data = { "session": session };
        var req = {
            method: 'POST',
            data: data,
            headers: {'Content-Type': 'application/json'},
            url: '/api/myquiz/answers/'
        }

        $http(req).success(
            function () {
                quiz();
            });
    }

和C#代码:

    [Route("answers")]
    [HttpPost]
    public IActionResult AnswerPost([FromBody] string session) {

       ...

    }

Chrome 控制台:

Request URL:http://localhost:39634/api/myquiz/answers/
Request Headers
Provisional headers are shown
Accept:application/json, text/plain, */*
Content-Type:application/json
Origin:http://localhost:39634
Referer:http://localhost:39634/Team/Index
User-Agent:Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/40.0.2214.93 Safari/537.36
Request Payload
{session: "92dfb7e432224702a553c98c294b29cf"}
session: "92dfb7e432224702a553c98c294b29cf"

Answer 1

您正在向 WebApi 发布一个对象:

var data = { "session": session };

这就是说您正在传递一个具有 session 属性的对象。你告诉你的 WebApi 方法期望的是一个字符串:

public IActionResult AnswerPost([FromBody] string session)

不是一个对象。我认为如果您将代码更改为:

$scope.send = function () {
        //var data = { "session": session };
        var req = {
            method: 'POST',
            data: session,
            headers: {'Content-Type': 'application/json'},
            url: '/api/myquiz/answers/'
        }

        $http(req).success(
            function () {
                quiz();
            });
    }

它应该可以工作。希望这可以帮助。不过，如果您将来要将更多参数传递给该函数，我会创建一个 C# 对象以传递给 Controller ​​。像这样:

public class AnswerPost
{
  public string Session {get; set;}
}

然后将 Controller 方法更新为如下所示:

[Route("answers")]
    [HttpPost]
    public IActionResult AnswerPost([FromBody] AnswerPost answerpost) {
...
}