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.NET Core C#

Box.com Streaming Upload File

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Demonstrates how to upload a file to box.com, streaming the file directly from the filesystem.

Note: This example requires a fix that is included in Chilkat v9.5.0.70 and above.

Chilkat .NET Core C# Downloads

.NET Core C#
bool success = false;

// This requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

Chilkat.Rest rest = new Chilkat.Rest();

//   Provide a previously obtained OAuth2 access token.
Chilkat.OAuth2 oauth2 = new Chilkat.OAuth2();
oauth2.AccessToken = "BOX_ACCESS_TOKEN";
rest.SetAuthOAuth2(oauth2);

// First, make the initial connection.
// A single REST object, once connected, can be used for many Box REST API calls.
// The auto-reconnect indicates that if the already-established HTTPS connection is closed,
// then it will be automatically re-established as needed.
bool bAutoReconnect = true;

// ----------------------------------------------------------------------
// IMPORTANT: Note that the domain is "upload.box.com", not "api.box.com"
// ----------------------------------------------------------------------
success = rest.Connect("upload.box.com",443,true,bAutoReconnect);
if (success != true) {
    Debug.WriteLine(rest.LastErrorText);
    return;
}

// The request body uses the "multipart/form-data" format to transmit two "parts". 
// The first part is called "attributes" and contains a JSON object with information about the file, including the name of the file 
// and the ID of the parent folder. The second part contains the contents of the file. 
// (Note that the name of the second "part" is ignored.)

rest.AddHeader("Content-Type","multipart/form-data");

// Provide the content for each part of the request...

// First the JSON attributes.  Use "0" for the root folder.
//   {"name":"hedgehogs.jpg", "parent":{"id":"0"}}
Chilkat.JsonObject jsonAttr = new Chilkat.JsonObject();
jsonAttr.UpdateString("name","hedgehogs.jpg");
jsonAttr.UpdateString("parent.id","0");

rest.PartSelector = "1";
rest.AddHeader("Content-Disposition","form-data; name=\"attributes\"; ");
rest.SetMultipartBodyString(jsonAttr.Emit());

// The upload will stream directly from a file.
rest.PartSelector = "2";
rest.AddHeader("Content-Disposition","form-data; name=\"file\"; filename=\"hedgehogs.jpg\"");
// "application/octet-stream" can be safely used for any type file..
rest.AddHeader("Content-Type","application/octet-stream");

// IMPORTANT: This example requires Chilkat v9.5.0.70 or later, for a fix that was made in
// multipart/streaming uploads. 
Chilkat.Stream fileStream = new Chilkat.Stream();
fileStream.SourceFile = "qa_data/jpg/hedgehogs.jpg";
rest.SetMultipartBodyStream(fileStream);

// Restore the PartSelector to "0" (for safety, in case something else sends another request on this object)
rest.PartSelector = "0";

// Send the multipart/form-data request, which uploads the file by streaming directly from the filesystem.
string responseBody = rest.FullRequestMultipart("POST","/api/2.0/files/content");
if (rest.LastMethodSuccess != true) {
    Debug.WriteLine(rest.LastErrorText);
    return;
}

// A 201 is received for a successful upload
if (rest.ResponseStatusCode != 201) {
    Debug.WriteLine("Box.com upload failed.");
    Debug.WriteLine("Request header:");
    Debug.WriteLine(rest.LastRequestHeader);
    Debug.WriteLine("---");
    Debug.WriteLine("Response status code = " + Convert.ToString(rest.ResponseStatusCode));
    Debug.WriteLine("Response body:");
    Debug.WriteLine(responseBody);
    return;
}

Debug.WriteLine("File uploaded.");