SharePoint 解決方案：SharePoint Server API無法上傳大於2GB的文檔

51CTO 博客地址：https://blog.51cto.com/13969817
博客園博客地址：https://www.cnblogs.com/bxapollo

很多大型企業使用很多數據平臺存儲數據，比如File Server，由於管理平臺較多，給IT造成很大壓力，因爲維護成本高，維護系統也多，所以爲了便於IT的管理，同時方便用戶統一數據平臺來訪問數據，IT會考慮將多個系統統一到一個強壯且安全的系統管理和維護。

今天跟Team在嘗試使用SharePoint Server API（Server Object Model）將File Server中的檔案上傳到SharePoint端，同時keep屬性和權限，但發現Server API無法上傳單個大於2GB檔案上到SharePoint Server 2019。

調用Microsoft.SharePoint.dll的方法：Microsoft.SharePoint.SPFileCollection.Add(SPResourcePath filePath, Stream file, SPFileCollectionAddParameters parameters)

Bug分析如下：通過反射發現裏面有個很明顯的bug，屬於Microsoft.SharePoint.dll內部方法限制

解決方案：使用SharePoint Client API(Client Object model)來完成大於2GB的數據上載，具體Sample Code如下所示：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Security;
using System.IO;
using System.Net;
using Microsoft.SharePoint.Client;
using Microsoft.SharePoint.Client.Administration;
using Microsoft.SharePoint.Client.Application;
namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            try
            {
                ClientContext context = new ClientContext("http://contoso-sp2019/sites/Test");
                string userName = "XXXX";
                string pwd = "XXXXX";
                string domain = "contoso.com";
                SecureString pwdd = new SecureString();
                pwd.ToList().ForEach(pwdd.AppendChar);
                //SharePointOnlineCredentials credential = new SharePointOnlineCredentials(userName, pwdd);
                NetworkCredential credential = new NetworkCredential(userName, pwdd, domain);
                context.Credentials = credential;
                List library = context.Web.GetList("http://contoso-sp2019/sites/Test/Shared%20Documents");
                context.Load(library);
                context.ExecuteQuery();
                FileCreationInformation fileInfo = new FileCreationInformation();
                fileInfo.Url = "http://contoso-sp2019/sites/Test/Shared%20Documents/abc.zip";
                fileInfo.Content = new byte[0];
                Microsoft.SharePoint.Client.File f = library.RootFolder.Files.Add(fileInfo);
                context.Load(f);
                context.ExecuteQuery();
                Guid uploadId = Guid.NewGuid();
                using (FileStream fs = new FileStream("abc.zip", FileMode.Open))
                {
                    byte[] buffer = new byte[1 * 1024 * 1024];
                    Byte[] lastBuffer = null;
                    long fileoffset = 0;
                    long totalBytesRead = 0;
                    int bytesRead;
                    bool first = true;
                    bool last = false;
                    while ((bytesRead = fs.Read(buffer, 0, buffer.Length)) > 0)
                    {
                        totalBytesRead = totalBytesRead + bytesRead;
                        if (totalBytesRead == fs.Length)
                        {
                            last = true;
                            lastBuffer = new byte[bytesRead];
                            Array.Copy(buffer, 0, lastBuffer, 0, bytesRead);
                        }
                        if (first)
                        {
                            using (MemoryStream contentStream = new MemoryStream())
                            {     
                                using (MemoryStream s = new MemoryStream(buffer))
                                {
                                    ClientResult<long> bytesUploaded = f.StartUpload(uploadId, s);
                                    context.ExecuteQuery();
                                    fileoffset = bytesUploaded.Value;
                                }
                                first = false;
                            }
                        }
                        else
                        {
                            if (last)
                            {
                                using (MemoryStream ss = new MemoryStream(lastBuffer))
                                {
                                    f.FinishUpload(uploadId, fileoffset, ss);
                                    context.ExecuteQuery();
                                    break;
                                }
                            }
                            else
                            {
                                using (MemoryStream ss = new MemoryStream(buffer))
                                {
                                    ClientResult<long> bytesUploaded = f.ContinueUpload(uploadId, fileoffset, ss);
                                    context.ExecuteQuery();
                                    fileoffset = bytesUploaded.Value;
                                }
                            }
                        }
                    }
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.ToString());
            }
        }
    }
}

這裏分享此解決方案，希望對大家日後有所幫助，如果有疑問，歡迎線下交流。