c# - 检查 Graph API 文件夹是否存在

Question

我正在使用 Microsoft Graph API，我正在创建一个文件夹，如下所示:

var driveItem = new DriveItem
{
    Name = Customer_Name.Text + Customer_LName.Text,
    Folder = new Folder
    {
    },
    AdditionalData = new Dictionary<string, object>()
    {
        {"@microsoft.graph.conflictBehavior","rename"}
    }
};

var newFolder = await App.GraphClient
  .Me
  .Drive
  .Items["id-of-folder-I-am-putting-this-into"]
  .Children
  .Request()
  .AddAsync(driveItem);

我的问题是如何检查此文件夹是否存在以及它是否获取文件夹的 ID？

Answer 1

Graph API 提供了一个 search facility ，您可以利用它来查明某个项目是否存在。您可以选择先运行搜索，然后在未找到任何内容的情况下创建一个项目，或者您可以按照 @Matt.G 的建议并尝试 nameAlreadyExists异常:

        var driveItem = new DriveItem
        {
            Name = Customer_Name.Text + Customer_LName.Text,
            Folder = new Folder
            {
            },
            AdditionalData = new Dictionary<string, object>()
            {
                {"@microsoft.graph.conflictBehavior","fail"}
            }
        };

        try
        {
            driveItem = await graphserviceClient
                .Me
                .Drive.Root.Children
                .Items["id-of-folder-I-am-putting-this-into"]
                .Children
                .Request()
                .AddAsync(driveItem);
        }
        catch (ServiceException exception)
        {
            if (exception.StatusCode == HttpStatusCode.Conflict && exception.Error.Code == "nameAlreadyExists")
            {
                var newFolder = await graphserviceClient
                    .Me
                    .Drive.Root.Children
                    .Items["id-of-folder-I-am-putting-this-into"]
                    .Search(driveItem.Name) // the API lets us run searches https://learn.microsoft.com/en-us/graph/api/driveitem-search?view=graph-rest-1.0&tabs=csharp
                    .Request()
                    .GetAsync();
                // since the search is likely to return more results we should filter it further
                driveItem = newFolder.FirstOrDefault(f => f.Folder != null && f.Name == driveItem.Name); // Just to ensure we're finding a folder, not a file with this name
                Console.WriteLine(driveItem?.Id); // your ID here
            }
            else
            {
                Console.WriteLine("Other ServiceException");
                throw;// handle this
            }
        }

The query text used to search for items. Values may be matched across several fields including filename, metadata, and file content.

你可以玩with search query并做类似 filename=<yourName> 的事情或可能检查文件类型(我想这对您的特定情况没有帮助，但为了完整起见我会提到它)