共享点/休息和元数据

Question

I am doing some basic Rest/http calls to a sharepoint site to upload documents. See code below.

This works like a charm, but it only creates the file with the name given and the content. Is there a way to manipulate the meta data in sharepoint via the REST/http interface?

I also tried using the oData protocol which makes it easy to alter metadata, but that required me to add a service reference and use the generated classes, very nice, but not the flexibility I need. Any suggestions?

byte[] bytesToSend = // get bytes from a file somewhere
WebRequest req = WebRequest.Create(new Uri("https://mysharepoint/sites/mysite/file.txt"));
req.Method = "PUT";
req.Credentials = new NetworkCredential("USR","passwd","Domain");
MemoryStream ms = new MemoryStream(bytesToSend);
ms.CopyTo(req.GetRequestStream());
HttpWebResponse resp = (HttpWebResponse)req.GetResponse();
if (resp.StatusCode.Equals(HttpStatusCode.OK) || resp.StatusCode.Equals(HttpStatusCode.Created))
{       // ... Ok done uploading.

Answer 1

Once you have uploaded the file if you search the response data you can find a server reply that contains the ID assigned to the file in SharePoint. With this ID we can make a second rest call to update that item and its metadata.

if (response.IsSuccessStatusCode)
{
    var info = response.Content.ReadAsStringAsync();
    JsonObject d = JsonValue.Parse(info.Result).GetObject();
    string id = d["d"].GetObject()["ListItemAllFields"].GetObject().GetNamedValue("ID").Stringify();

    client = new HttpClient(new HttpClientHandler() { UseDefaultCredentials = true });
    client.BaseAddress = new System.Uri(url);
    client.DefaultRequestHeaders.Clear();
    client.DefaultRequestHeaders.Add("X-RequestDigest", digest);
    client.DefaultRequestHeaders.Add("X-HTTP-Method", "MERGE");
    client.DefaultRequestHeaders.Add("IF-MATCH", "*");
    HttpContent strContent = new StringContent(String.Concat("{ '__metadata': { 'type': 'SP.List' }, 'Title': '", filename, "' }"));
    strContent.Headers.ContentType = new MediaTypeHeaderValue("application/json");
    strContent.Headers.ContentType.Parameters.Add(new NameValueHeaderValue("odata", "verbose"));
    HttpResponseMessage updateResponse = await client.PostAsync(String.Concat("_api/web/lists/GetByTitle('Project Photos')/Items(", id, ")"), strContent);
    updateResponse.EnsureSuccessStatusCode();
    if (updateResponse.IsSuccessStatusCode)
    {

    }
}

I have more examples here of working with SharePoint REST using the HttpClient:

https://arcandotnet.wordpress.com/2015/04/01/sharepoint-2013-rest-services-using-c-and-the-httpclient-for-windows-store-apps/