Ajax调用web API成功，但未找到C#调用web API 404

我有以下web API方法：

[System.Web.Http.RoutePrefix("api/PurchaseOrder")]
public class PurchaseOrderController : ApiController
{
    private static ILog logger = log4net.LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);

    [System.Web.Http.Route("PagingCriticalPart")]
    [System.Web.Http.HttpPost]
    public JsonResult PagingCriticalPart([FromBody] Helper.DataTablesBase model)
    {
        logger.Info("PagingCriticalPart");
        JsonResult jsonResult = new JsonResult();
        try
        {
            if (model == null) { logger.Info("model is null."); }

            int filteredResultsCount;
            int totalResultsCount;
            var res = BLL.PurchaseOrderHandler.PagingCriticalPart(model, out filteredResultsCount, out totalResultsCount);

            var result = new List<Models.T_CT2_CriticalPart>(res.Count);
            foreach (var s in res)
            {
                // simple remapping adding extra info to found dataset
                result.Add(new Models.T_CT2_CriticalPart
                {
                    active = s.active,
                    createBy = s.createBy,
                    createdDate = s.createdDate,
                    id = s.id,
                    modifiedBy = s.modifiedBy,
                    modifiedDate = s.modifiedDate,
                    partDescription = s.partDescription,
                    partNumber = s.partNumber
                });
            };

            jsonResult.Data = new
            {
                draw = model.draw,
                recordsTotal = totalResultsCount,
                recordsFiltered = filteredResultsCount,
                data = result
            };
            return jsonResult;
        }
        catch (Exception exception)
        {
            logger.Error("PagingCriticalPart", exception);
            string exceptionMessage = ((string.IsNullOrEmpty(exception.Message)) ? "" : Environment.NewLine + Environment.NewLine + exception.Message);
            string innerExceptionMessage = ((exception.InnerException == null) ? "" : ((string.IsNullOrEmpty(exception.InnerException.Message)) ? "" : Environment.NewLine + Environment.NewLine + exception.InnerException.Message));
            jsonResult.Data = new
            {
                draw = model.draw,
                recordsTotal = 0,
                recordsFiltered = 0,
                data = new { },
                error = exception.Message
            };
            return jsonResult;
        }
    }

    [System.Web.Http.Route("UploadRawMaterialData")]
    [System.Web.Http.HttpPost]
    public JsonResult UploadRawMaterialData(string rawMaterialSupplierData)
    {
        JsonResult jsonResult = new JsonResult();
        jsonResult.Data = new
        {
            uploadSuccess = true
        };
        return jsonResult;
    }
}

但是当从c#调用UploadRawMaterialData时，它得到错误：404未找到

var data = Newtonsoft.Json.JsonConvert.SerializeObject(rawMaterialVendorUploads);
string apiURL = @"http://localhost/ControlTower2WebAPI/api/PurchaseOrder/UploadRawMaterialData";
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(apiURL);
request.UseDefaultCredentials = true;
request.Method = "POST";
request.ContentType = "application/json";
request.ContentLength = data.Length;
using (Stream webStream = request.GetRequestStream())
using (StreamWriter requestWriter = new StreamWriter(webStream, System.Text.Encoding.ASCII))
{
    requestWriter.Write(data);
}

try
{
    WebResponse webResponse = request.GetResponse();
    using (Stream webStream = webResponse.GetResponseStream() ?? Stream.Null)
    using (StreamReader responseReader = new StreamReader(webStream))
    {
        string response = responseReader.ReadToEnd();
    }
}
catch (Exception exception)
{

}

使用邮递员返回类似错误：

{
    "Message": "No HTTP resource was found that matches the request URI 'http://localhost/ControlTower2WebAPI/api/PurchaseOrder/UploadRawMaterialData'.",
    "MessageDetail": "No action was found on the controller 'PurchaseOrder' that matches the request."
}

但如果我用邮递员这样称呼它，没有问题：

http://localhost/ControlTower2WebAPI/api/PurchaseOrder/UploadRawMaterialData?rawMaterialSupplierData=test

---

我遗漏了什么？

在您的

UploadRawMaterialData

方法的方法签名中，您遗漏了

[FromBody]

属性。对于

UploadRawMaterialData

方法，所有在正文中包含数据的

POST请求都需要此在方法签名中，您缺少
[FromBody]
属性。所有在正文中包含数据的
POST
请求都需要这个您有两个选择

按照其他答案中的建议使用[FromBody]
让你的Url像这样
string queryData=“test”
字符串apiUrl=”http://localhost/ControlTower2WebAPI/api/PurchaseOrder/UploadRawMaterialData?rawMaterialSupplierData=“+试验

基本上，
发送查询数据的方式才是最重要的，如果不指定[FromBody]属性，数据将在URI中传递，并且必须修改URI。
您有两个选项

按照其他答案中的建议使用[FromBody]
让你的Url像这样
string queryData=“test”
字符串apiUrl=”http://localhost/ControlTower2WebAPI/api/PurchaseOrder/UploadRawMaterialData?rawMaterialSupplierData=“+试验

基本上，
发送查询数据的方式才是最重要的，如果不指定[FromBody]属性，数据将在URI中传递，URI必须修改。
您的ajax和C#代码没有调用相同的方法，请尝试从ajax调用相同的方法，看看是否得到一个404，而且您似乎缺少了
[FromBody]
在
UploadRawMaterialData
方法签名中您的ajax和C#代码没有调用同一个方法，请尝试从ajax调用同一个方法，看看您是否得到了一个404，而且您似乎缺少
UploadRawMaterialData
方法签名中的
[FromBody]
http://localhost/ControlTower2WebAPI/api/PurchaseOrder/UploadRawMaterialData?rawMaterialSupplierData=test