Upload local file to SharePoint Online using HttpWebRequest - rest

Question

I'm trying to upload a file to a SharePoint online site that I have permissions for, I have tried using an HttpWebRequest to get an XDocument to allow me to upload a file but when I call an HttpWebResponse I get the error "The underlying connection was closed: An unexpected error occurred on a receive."
I'm unable to use SharePoint client object model as this app is to be used on PCs that don't have a SharePoint installation.

Answer 1

You will need to create a digest:
HttpClient client = new HttpClient(new HttpClientHandler() { UseDefaultCredentials = true });
client.BaseAddress = new System.Uri(url);
string cmd = "_api/contextinfo";
client.DefaultRequestHeaders.Add("Accept", "application/json;odata=verbose");
client.DefaultRequestHeaders.Add("ContentType", "application/json");
client.DefaultRequestHeaders.Add("ContentLength", "0");
StringContent httpContent = new StringContent("");
var response = client.PostAsync(cmd, httpContent).Result;
if (response.IsSuccessStatusCode)
{
string content = response.Content.ReadAsStringAsync().Result;
JsonObject val = JsonValue.Parse(content).GetObject();
JsonObject d = val.GetNamedObject("d");
JsonObject wi = d.GetNamedObject("GetContextWebInformation");
retVal = wi.GetNamedString("FormDigestValue");
}
Then you can use the following example to upload the file and retrieve its metadata from the http response:
HttpClient client = new HttpClient(new HttpClientHandler() { UseDefaultCredentials = true });
client.BaseAddress = new System.Uri(url);
client.DefaultRequestHeaders.Clear();
client.DefaultRequestHeaders.Add("Accept", "application/json;odata=verbose");
client.DefaultRequestHeaders.Add("X-RequestDigest", digest);
client.DefaultRequestHeaders.Add("X-HTTP-Method", "POST");
client.DefaultRequestHeaders.Add("binaryStringRequestBody", "true");
IRandomAccessStream fileStream = await path.OpenAsync(FileAccessMode.Read);
var reader = new DataReader(fileStream.GetInputStreamAt(0));
await reader.LoadAsync((uint)fileStream.Size);
Byte[] content = new byte[fileStream.Size];
reader.ReadBytes(content);
ByteArrayContent file = new ByteArrayContent(content);
HttpResponseMessage response = await client.PostAsync(String.Concat("_api/web/lists/getByTitle('Project Photos')/RootFolder/Files/add(url='", filename, ".jpg',overwrite='true')?$expand=ListItemAllFields"), file);
response.EnsureSuccessStatusCode();
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();
}