Question

我尝试从我的客户端应用程序（WPF应用程序）向SharePoint Online（基于声明的Auth站点）发送Post请求。在这种情况下，它应该是对ListItem的更新，以更改标题＆＃39;到＆＃39;测试＆＃39;。

我通过MsOnlineClaimsHelper Class检索CookieContainer 它成功地返回了一个身份验证令牌。

但是当我尝试发送请求时，响应为The remote server returned an error: (403) Forbidden.

WebRequest代码

try
{
    var claimshelper = new MsOnlineClaimsHelper(baseUrl, _userName, _password);
    var request = (HttpWebRequest)WebRequest.Create(baseUrl + "/" + url);

    request.CookieContainer = claimshelper.CookieContainer;
    request.Method = "POST";
    request.Headers.Add("X-HTTP-Method", "MERGE");
    request.Headers.Add("If-Match", "*");
    request.Accept = "application/json;odata=verbose";

    using (var streamWriter = new StreamWriter(request.GetRequestStream()))
    {
        streamWriter.Write(json);
        streamWriter.Flush();
    }

    var webResp = request.GetResponse() as HttpWebResponse;
    var theData = new StreamReader(webResp.GetResponseStream(), true);
    string payload = theData.ReadToEnd();
}
catch (Exception ex)
{


}

Rest Url：

/_api/lists/getbytitle('SampleList')/items(1)

Json Payload：

string json = "{ '__metadata': { 'type': 'SP.Data.SampleListListItem' }, 'Title': 'Test'}";

错误：

The remote server returned an error: (403) Forbidden.

Answer 1

发生此错误，因为SharePoint 2013 REST服务要求用户在每个Request Digest，create和update操作中包含delete值。然后，SharePoint使用此值来标识非正版请求。

如何提供请求摘要值

在MsOnlineClaimsHelper class（MsOnlineClaimsHelper.cs文件）中添加以下方法以请求表单摘要值：

/// <summary>
/// Request Form Digest value
/// </summary>
/// <returns></returns>
private string GetFormDigest()
{
    var endpoint = "/_api/contextinfo";
    var request = (HttpWebRequest) WebRequest.Create(_host.AbsoluteUri + endpoint);

    request.CookieContainer = new CookieContainer();
    request.Method = "POST";
    //request.Accept = "application/json;odata=verbose";
    request.ContentLength = 0;

    using (var response = (HttpWebResponse)request.GetResponse())
    {
         using (var reader = new StreamReader(response.GetResponseStream()))
         {
             var result = reader.ReadToEnd();

             // parse the ContextInfo response
             var resultXml = XDocument.Parse(result);

             // get the form digest value
             var e = from e in resultXml.Descendants()
                                 where e.Name == XName.Get("FormDigestValue", "http://schemas.microsoft.com/ado/2007/08/dataservices")
                            select e;
             _formDigest = e.First().Value;   
         }
    }
    return _formDigest;
}

和FormDigest属性：

private string _formDigest;
public string FormDigest
{
    get
    {
       if (_formDigest == null || DateTime.Now > _expires)
       {
           return GetFormDigest();
       }
       return _formDigest;
    }
}

如何使用SharePoint 2013 REST API

对ListItem执行更新操作

以下示例演示了如何使用提供的实现来请求表单摘要来执行列表项的更新

要点：

X-RequestDigest标头用于指定表单摘要值
必须指定请求Content Type

示例：

var userName = "username@contoso.onmicrosoft.com";
var password = "password";
var payload = "{ '__metadata': { 'type': 'SP.Data.TasksListItem' }, 'Title': 'New Tasl'}";  //for a Task Item


try
{
    var claimshelper = new MsOnlineClaimsHelper(baseUrl, _userName, _password);
    var request = (HttpWebRequest)WebRequest.Create(baseUrl + "/" + endpointUrl);

    request.CookieContainer = claimshelper.CookieContainer;
    request.Headers.Add("X-RequestDigest", claimshelper.FormDigest);
    request.Method = "POST";
    request.Headers.Add("X-HTTP-Method", "MERGE");
    request.Headers.Add("If-Match", "*");
    request.Accept = "application/json;odata=verbose";
    request.ContentType = "application/json;odata=verbose";

    using (var writer = new StreamWriter(request.GetRequestStream()))
    {
        writer.Write(payload);
        writer.Flush();
    }

    var response = request.GetResponse() as HttpWebResponse;
    //...
 }
 catch (Exception ex)
 {
    //Error handling goes here.. 
 }

使用身份验证令牌休息后呼叫

1 个答案:

如何提供请求摘要值

如何使用SharePoint 2013 REST API