javascript - 带有单个字符串参数的 WebApi 2 POST 不起作用

Question

我有以下 Controller :

public class ValuesController : ApiController
{
    // POST api/values
    public IHttpActionResult Post(string filterName)
    {
        return new JsonResult<string>(filterName, new JsonSerializerSettings(), Encoding.UTF8, this);

    }
}

WebApi 配置

config.Routes.MapHttpRoute(
    name: "DefaultApi",
    routeTemplate: "api/{controller}/{id}",
    defaults: new { id = RouteParameter.Optional });

我用这个js代码调用api

$.ajax(
{
    url: "/api/values/",
    type: "POST",
    dataType: 'json',
    data: { filterName: "Dirty Deeds" },
    success: function (result) {
        console.log(result);
    },
    error: function (xhr, status, p3, p4) {
        var err = "Error " + " " + status + " " + p3;
        if (xhr.responseText && xhr.responseText[0] == "{")
            err = JSON.parse(xhr.responseText).message;
        console.log(err);
    }
});

我得到一个 405 方法不允许(post)

Answer 1

c#

public class ValuesController : ApiController
{
    // POST api/values
    [HttpPost] // added attribute
    public IHttpActionResult Post([FromBody] string filterName) // added FromBody as this is how you are sending the data
    {
        return new JsonResult<string>(filterName, new JsonSerializerSettings(), Encoding.UTF8, this);
    }

JavaScript

$.ajax(
{
    url: "/api/Values/", // be consistent and case the route the same as the ApiController
    type: "POST",
    dataType: 'json',
    data: "=Dirty Deeds", // add an = sign
    success: function (result) {
        console.log(result);
    },
    error: function (xhr, status, p3, p4) {
        var err = "Error " + " " + status + " " + p3;
        if (xhr.responseText && xhr.responseText[0] == "{")
            err = JSON.parse(xhr.responseText).message;
        console.log(err);
    }
});

说明

因为您只发送一个值，所以在它前面添加 = 符号，这样它将被视为表单编码。如果您想清楚地表明这是您对 ajax 调用所做的，您还可以添加内容类型。

contentType: 'application/x-www-form-urlencoded'

或者，您也可以通过 URL 发送内容，或者将内容包装在服务器上的对象以及 ajax 调用中，然后将其字符串化。

public class Filter {
    public string FilterName {get;set;}
}

public class ValuesController : ApiController
{
    // POST api/values
    [HttpPost] // added attribute
    public IHttpActionResult Post([FromBody] Filter filter) // added FromBody as this is how you are sending the data
    {
        return new JsonResult<string>(filter.FilterName, new JsonSerializerSettings(), Encoding.UTF8, this);
    }

JavaScript

$.ajax(
{
    url: "/api/Values/", // be consistent and case the route the same as the ApiController
    type: "POST",
    dataType: 'json',
    contentType: 'application/json',
    data: JSON.stringify({FilterName: "Dirty Deeds"}), // send as json
    success: function (result) {
        console.log(result);
    },
    error: function (xhr, status, p3, p4) {
        var err = "Error " + " " + status + " " + p3;
        if (xhr.responseText && xhr.responseText[0] == "{")
            err = JSON.parse(xhr.responseText).message;
        console.log(err);
    }
});