调用Web服务“ 400错误的请求”错误

Question

我正在尝试在我的C＃ASP.Net MVC3应用程序中调用Web服务。 这是源代码：

public string getCourseSchedule()
{
    string url = "http://192.168.1.198:15014/ShoppingCart2/CourseSchedule";
    string data = "Months&StatesMX&Zip=&Miles=&ProgramCodes=&EventCode=&PaginationStart=1&PaginationLimit=3";
    byte[] bytes          = Encoding.UTF8.GetBytes(data);
    var myReq             = (HttpWebRequest)WebRequest.Create(url);
    myReq.Method          = "POST";
    myReq.ContentLength   = data.Length;
    myReq.ContentType = "application/x-www-form-urlencoded; charset=UTF-8";
    string responseString = "";

    using (Stream requestStream = myReq.GetRequestStream())
    {
        requestStream.Write(bytes, 0, bytes.Length);
    }

    using (HttpWebResponse response = (HttpWebResponse)myReq.GetResponse())
    {
        HttpStatusCode statusCode = response.StatusCode;
        if (statusCode == HttpStatusCode.OK)
        {
            responseString = new StreamReader(response.GetResponseStream()).ReadToEnd();
        }
    }
    return responseString;
}

该代码返回“ 400 Bad Request”错误。 这就是我在javascript中执行此操作的方式，并且有效。

Mexico_Schedule: {"Months": null,
                  "States": [{"State: "MX"}],
                  "Zip": "",
                  "Miles": "",
                  "ProgramCodes": null,
                  "EventCode": null
                  "PaginationStart": 1,
                  "PaginationLimit": 3
};

$.ajax({
    async:       true,
    cache:       false,
    type:        'POST',
    contentType: 'application/x-www-form-urlencoded; charset=UTF-8',
    url:         "http://192.168.1.198:15014/ShoppingCart2/CourseSchedule",
    data:        JSON.stringify(Mexico_Schedule),
    dataType:    'json',
    success: function (data) {
        console.log('Fired when the request is successful');
        // Do something with results
    }
});

为了使C＃版本正常工作，我需要进行哪些修改？

Answer 1

只需将您的data （使用Json.Net ）形成为：

var obj = new
{
    States = new[] { new{ State = "MX" } },
    Zip = "",
    Miles = "",
    PaginationStart = 1,
    PaginationLimit = 3
};

string data = JsonConvert.SerializeObject(obj);

Answer 2

我宁愿尝试使用WebClient和JSON serializer程序来简化您的代码：

public string getCourseSchedule()
{
    using (var client = new WebClient())
    {
        client.Headers[HttpRequestHeader.ContentType] = "apoplication/json";
        var url = "http://192.168.1.198:15014/ShoppingCart2/CourseSchedule";
        var json = new JavaScriptSerializer().Serialize(new
        {
            States = new[] { new { State = "MX" } },
            Zip = "",
            Miles = "",
            PaginationStart = 1,
            PaginationLimit = 3
        });
        byte[] data = Encoding.UTF8.GetBytes(json);
        byte[] result = client.UploadData(url, data);
        return Encoding.UTF8.GetString(result);
    }
}

另外，如果您不想使用内置的.NET JavaScriptSerializer类，则可以使用第三方，例如JSON.NET：

string json = JsonConvert.SerializeObject(new
{
    States = new[] { new { State = "MX" } },
    Zip = "",
    Miles = "",
    PaginationStart = 1,
    PaginationLimit = 3
});

Answer 3

您指定了错误的内容类型。 您正在发布x-www-form-urlencoded数据，但是将content-type设置为“ application / json”使数据与您的内容类型匹配，反之亦然。