2017-10-09 39 views
2

我有一个可以完美发布数据的POST方法。HttpClient.PutAsync - “实体只允许使用JSON Content-Type标题进行写入”

看看文档看起来PATCH(或PUT)应该看起来完全一样,只需使用PutAsync而不是PostAsync

那么做,只是我收到以下错误:

+  postResponse {StatusCode: 400, ReasonPhrase: 'Bad Request', Version: 1.1, Content: System.Net.Http.NoWriteNoSeekStreamContent, Headers: 
{ 
    Cache-Control: private 
    Date: Mon, 09 Oct 2017 12:19:28 GMT 
    Transfer-Encoding: chunked 
    request-id: 60370069-f7c4-421d-842e-b1ee8573c2c2 
    client-request-id: 60370069-f7c4-421d-842e-b1ee8573c2c2 
    x-ms-ags-diagnostic: {"ServerInfo":{"DataCenter":"North Europe","Slice":"SliceB","ScaleUnit":"002","Host":"AGSFE_IN_7","ADSiteName":"DUB"}} 
    Duration: 3.2626 
    Content-Type: application/json 
}} System.Net.Http.HttpResponseMessage 

和响应:

Entity only allows writes with a JSON Content-Type header

足够的错误我也可以看到这个肯定:

ContentType {text/plain; charset=utf-8} System.Net.Http.Headers.MediaTypeHeaderValue 

所以这个错误是有道理的,但是,我确实告诉它使用JSON,并且它在我的POST方法中使用相同的cod E:

public async Task UpdateToGraph(object UnSerializedContent, string relativeUrl) 
{ 
    string accessToken = await _tokenManager.GetAccessTokenAsync(); 
    HttpContent content = new StringContent(JsonConvert.SerializeObject(UnSerializedContent)); 

    Client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", accessToken); 
    Client.DefaultRequestHeaders.Add("ContentType", "application/json"); 

    string endpoint = "https://graph.microsoft.com/v1.0" + relativeUrl; 
    var postResponse = Client.PutAsync(endpoint, content).Result; 

    string serverResponse = postResponse.Content.ReadAsStringAsync().Result; 
} 

回答

3

您可以使用.{Verb}AsJsonAsync HttpClientExtensions方法。

public async Task UpdateToGraph(object UnSerializedContent, string relativeUrl) { 
    var accessToken = await _tokenManager.GetAccessTokenAsync(); 

    Client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", accessToken); 
    Client.DefaultRequestHeaders.Add("ContentType", "application/json"); 

    var endpoint = "https://graph.microsoft.com/v1.0" + relativeUrl; 
    var postResponse = await Client.PutAsJsonAsync(endpoint, UnSerializedContent); 

    var serverResponse = await postResponse.Content.ReadAsStringAsync(); 
} 

还要注意/正确使用异步电动机通过不混合阻塞调用像.Resultasync方法,因为这可能会导致死锁等待。

参考Async/Await - Best Practices in Asynchronous Programming

+0

谢谢'HttpClient的不包含PutAsJsonAsync'的定义,认为我失去了一些东西? :) –

+0

@Green_qaue你可能缺少一个参考https://msdn.microsoft.com/en-us/library/system.net.http.httpclientextensions.putasjsonasync(v=vs.118).aspx – Nkosi

+0

找到它,谢谢:)另一个问题是,如果我删除'.Result',我不能再访问'postResponse.Content' –

1

使用的StringContent构造函数中设置内容类型:

HttpContent content = new StringContent(JsonConvert.SerializeObject(UnSerializedContent), System.Text.Encoding.UTF8, "application/json"); 

据我所知,你是不是要设置内容头请求对象上使用时, HttpClient的。