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6EHPS2
6 years agoExplorer | Level 3
ListFolderAsync() throws InvalidCastException when file or folder name is ISO-8601 date
Description
When a file or a folder exists with a name that is an ISO-8601 date (such as "2019-12-25T23:58:05"), the ListFolderAsync() method fails by throwing a System.InvalidCastException.
Steps to reproduce
- Create a folder test in the root folder of your Dropbox.
- Upload a file with the name 2019-12-25T23:58:05 to the folder /test or create a new folder with that name as a subfolder of the folder /test. Make sure that there is no file extension.
- Run the following C# program, after providing a valid access token:
public class Program { static void Main(string[] args) { using var dbx = new DropboxClient(oauth2AccessToken: "..."); var result = dbx.Files.ListFolderAsync( path: "/test" ).GetAwaiter().GetResult(); } }
Expected result
The method should return a list of Dropbox.Api.Files.Metadata objects, including one object representing the file or folder created above.
Actual result
The program crashes with the following exception:
System.InvalidCastException HResult=0x80004002 Message=Value '12/25/2019 23:58:05' is not valid System.String type Source=Dropbox.Api StackTrace: at Dropbox.Api.Stone.JsonReader.ReadValue[T]() at Dropbox.Api.Stone.JsonReader.Dropbox.Api.Stone.IJsonReader.ReadString() at Dropbox.Api.Stone.StringDecoder.Decode(IJsonReader reader) at Dropbox.Api.Files.FileMetadata.FileMetadataDecoder.SetField(FileMetadata value, String fieldName, IJsonReader reader) at Dropbox.Api.Stone.StructDecoder`1.DecodeFields(IJsonReader reader) at Dropbox.Api.Files.Metadata.MetadataDecoder.Decode(String tag, IJsonReader reader) at Dropbox.Api.Stone.UnionDecoder`1.DecodeFields(IJsonReader reader) at Dropbox.Api.Stone.StructDecoder`1.Decode(IJsonReader reader) at Dropbox.Api.Stone.ListDecoder`1.TryReadArrayItem(IJsonReader reader, IDecoder`1 decoder, T& value) at Dropbox.Api.Stone.ListDecoder`1.Decode(IJsonReader reader, IDecoder`1 itemDecoder) at Dropbox.Api.Stone.StructDecoder`1.ReadList[TItem](IJsonReader reader, IDecoder`1 itemDecoder) at Dropbox.Api.Files.ListFolderResult.ListFolderResultDecoder.SetField(ListFolderResult value, String fieldName, IJsonReader reader) at Dropbox.Api.Stone.StructDecoder`1.DecodeFields(IJsonReader reader) at Dropbox.Api.Stone.StructDecoder`1.Decode(IJsonReader reader) at Dropbox.Api.Stone.JsonReader.Read[T](String json, IDecoder`1 decoder) at Dropbox.Api.DropboxRequestHandler.<Dropbox-Api-Stone-ITransport-SendRpcRequestAsync>d__12`3.MoveNext() at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() in /_/src/System.Private.CoreLib/shared/System/Runtime/ExceptionServices/ExceptionDispatchInfo.cs:line 63 at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) in /_/src/System.Private.CoreLib/shared/System/Runtime/CompilerServices/TaskAwaiter.cs:line 180 at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) in /_/src/System.Private.CoreLib/shared/System/Runtime/CompilerServices/TaskAwaiter.cs:line 151 at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult() in /_/src/System.Private.CoreLib/shared/System/Runtime/CompilerServices/TaskAwaiter.cs:line 369 at DropboxUpload.Program.Main(String[] args) in C:\my\vs\repos\DropboxUpload\Program.cs:line 681 This exception was originally thrown at this call stack: Dropbox.Api.Stone.JsonReader.ReadValue<T>() Dropbox.Api.Stone.JsonReader.Dropbox.Api.Stone.IJsonReader.ReadString() Dropbox.Api.Stone.StringDecoder.Decode(Dropbox.Api.Stone.IJsonReader) Dropbox.Api.Files.FileMetadata.FileMetadataDecoder.SetField(Dropbox.Api.Files.FileMetadata, string, Dropbox.Api.Stone.IJsonReader) Dropbox.Api.Stone.StructDecoder<T>.DecodeFields(Dropbox.Api.Stone.IJsonReader) Dropbox.Api.Files.Metadata.MetadataDecoder.Decode(string, Dropbox.Api.Stone.IJsonReader) Dropbox.Api.Stone.UnionDecoder<T>.DecodeFields(Dropbox.Api.Stone.IJsonReader) Dropbox.Api.Stone.StructDecoder<T>.Decode(Dropbox.Api.Stone.IJsonReader) Dropbox.Api.Stone.ListDecoder<T>.TryReadArrayItem(Dropbox.Api.Stone.IJsonReader, Dropbox.Api.Stone.IDecoder<T>, out T) Dropbox.Api.Stone.ListDecoder<T>.Decode(Dropbox.Api.Stone.IJsonReader, Dropbox.Api.Stone.IDecoder<T>) ... [Call Stack Truncated]
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