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C#

Create Folder

See more Google Drive Examples

In the Drive API, a folder is essentially a file — one identified by the special folder MIME type application/vnd.google-apps.folder

See Google Drive Files: create for more details.

Also See Working with Folders for more details.

Chilkat C# Downloads

C#
bool success = false;

// Creating a folder is technically an upload of a 0-length file
// having a MIME type of "application/vnd.google-apps.folder"

success = true;

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

// This example uses a previously obtained access token having permission for the 
// Google Drive scope.

Chilkat.AuthGoogle gAuth = new Chilkat.AuthGoogle();
gAuth.AccessToken = "GOOGLE-DRIVE-ACCESS-TOKEN";

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

// Connect using TLS.
bool bAutoReconnect = true;
success = rest.Connect("www.googleapis.com",443,true,bAutoReconnect);

// Provide the authentication credentials (i.e. the access token)
rest.SetAuthGoogle(gAuth);

// A multipart upload to Google Drive needs a multipart/related Content-Type
rest.AddHeader("Content-Type","multipart/related");

// Specify each part of the request.

// The 1st part is JSON with information about the folder.
rest.PartSelector = "1";
rest.AddHeader("Content-Type","application/json; charset=UTF-8");

Chilkat.JsonObject json = new Chilkat.JsonObject();
json.AppendString("name","testFolder");
json.AppendString("description","A folder to contain test files.");
json.AppendString("mimeType","application/vnd.google-apps.folder");
rest.SetMultipartBodyString(json.Emit());

// The 2nd part would be the file content.
// Since this is a folder, skip the 2nd part entirely and go straight to the upload..

string jsonResponse = rest.FullRequestMultipart("POST","/upload/drive/v3/files?uploadType=multipart");
if (rest.LastMethodSuccess != true) {
    Debug.WriteLine(rest.LastErrorText);
    return;
}

// A successful response will have a status code equal to 200.
if (rest.ResponseStatusCode != 200) {
    Debug.WriteLine("response status code = " + Convert.ToString(rest.ResponseStatusCode));
    Debug.WriteLine("response status text = " + rest.ResponseStatusText);
    Debug.WriteLine("response header: " + rest.ResponseHeader);
    Debug.WriteLine("response JSON: " + jsonResponse);
    return;
}

// Show the JSON response.
json.Load(jsonResponse);

// Show the full JSON response.
json.EmitCompact = false;
Debug.WriteLine(json.Emit());

// A successful response looks like this:
// {
//   "kind": "drive#file",
//   "id": "0B53Q6OSTWYolY2tPU1BnYW02T2c",
//   "name": "testFolder",
//   "mimeType": "application/vnd.google-apps.folder"
// }

// Get the fileId:
Debug.WriteLine("fileId: " + json.StringOf("id"));