C#错误CS0117-当我使用Google Drive API时，文件不包含ReadAllText的定义

我试图使一些客户端上传文件到谷歌驱动器。我从一些网站复制了部分代码，但仍然有一个错误。错误号为CS0117，表示该文件不包含ReadAllText的定义。错误在第55行。谢谢你的回答。这是我的密码：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.IO;
using Google.Apis.Auth.OAuth2;
using Google.Apis.Drive.v3;
using File = Google.Apis.Drive.v3.Data.File;
using Google.Apis.Services;
using Google.Apis.Util.Store;

namespace IDK_client
{
    public partial class Form1 : Form
    {
        //Upload variables
        public bool uploadFilesSelected = false;
        public string uploadFileContent;

        //Google Drive connection variables
        static string[] Scopes = { DriveService.Scope.Drive };
        static string ApplicationName = "server";

        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            labelUploadFile.Visible = false;
        }    

        private void buttonUpload_Click(object sender, EventArgs e)
        {
            if(uploadFilesSelected == false)
            {
                try
                {
                    OpenFileDialog openFileDialogUpload = new OpenFileDialog();
                    openFileDialogUpload.CheckFileExists = true;
                    openFileDialogUpload.CheckPathExists = true;
                    openFileDialogUpload.InitialDirectory = @"C:\Users\";
                    openFileDialogUpload.RestoreDirectory = true;
                    openFileDialogUpload.Title = "Select file to upload...";
                    openFileDialogUpload.Filter = "All files (*.*)|*.*";
                    openFileDialogUpload.ShowDialog();
                    labelUploadFile.Text = openFileDialogUpload.SafeFileName;
                    uploadFileContent = File.ReadAllText(openFileDialogUpload.FileName);
                    labelUploadFile.Visible = true;
                    uploadFilesSelected = true;
                }
                catch
                {
                    MessageBox.Show("Can not open file.", "Warning", MessageBoxButtons.OKCancel, MessageBoxIcon.Warning);
                }

            }

            else if(uploadFilesSelected == false)
            {
                UserCredential credential;
                credential = GetCredentials();
                // Create Drive API service.
                var service = new DriveService(new BaseClientService.Initializer()
                {
                    HttpClientInitializer = credential,
                    ApplicationName = ApplicationName,
                });
                //uploadFile();
            }

        }

        public void uploadFile(string path, DriveService service)
        {
            var fileMetadata = new Google.Apis.Drive.v3.Data.File();
            fileMetadata.Name = Path.GetFileName(path);
            fileMetadata.MimeType = "txt";
            FilesResource.CreateMediaUpload request;
            using (var stream = new System.IO.FileStream(path, System.IO.FileMode.Open))
            {
                request = service.Files.Create(fileMetadata, stream, "txt");
                request.Fields = "id";
                request.Upload();
            }

            var file = request.ResponseBody;
        }

        private static UserCredential GetCredentials()
        {
            UserCredential credential;

            using (var stream = new FileStream("client_id.json", FileMode.Open, FileAccess.Read))
            {
                string credPath = System.Environment.GetFolderPath(System.Environment.SpecialFolder.Personal);

                credPath = Path.Combine(credPath, ".credentials/drive-dotnet-quickstart.json");

                credential = GoogleWebAuthorizationBroker.AuthorizeAsync(GoogleClientSecrets.Load(stream).Secrets, Scopes, "user", CancellationToken.None, new FileDataStore(credPath, true)).Result;
            // Console.WriteLine("Credential file saved to: " + credPath);
            }

            return credential;
        }
    }
}

---

很可能您还有其他名为

文件的文件

。用

System.IO.File.ReadAllText

完全限定它，我猜您可能有一个冲突的类。请尝试

System.IO.File.ReadAllText（…

Right.OP正在使用File=Google.api.Drive.v3.Data.File；