Question

我正在使用Microsoft.SharePoint.Client DLL在我的MVC C#项目中上传文件。

现在我使用下面的代码下载版本文件，但是找不到文件错误。

using (var clientContext = new ClientContext(_SharePointSiteURL))
{
    var onlineCredentials = new SharePointOnlineCredentials(_SharePointSiteUser, securePassword);
    clientContext.RequestTimeout = 10000000;
    clientContext.Credentials = onlineCredentials;

    var spFile = clientContext.Web.GetFileByServerRelativeUrl(System.IO.Path.Combine("/Shared Documents/ABC", "Test.pdf"));
    clientContext.Load(spFile);
    FileVersionCollection versions = spFile.Versions;
    clientContext.Load(versions);
    var oldVersions = clientContext.LoadQuery(versions.Where(v => v != null));
    clientContext.ExecuteQuery();
    if (oldVersions != null)
    {
        foreach (Microsoft.SharePoint.Client.FileVersion _version in oldVersions)
        {
            if (_version.VersionLabel == "2.0")
            {
                clientContext.Load(_version, item => item.Url);
                clientContext.ExecuteQuery();

                string vURL = _version.Url;
                Microsoft.SharePoint.Client.File oldFile = clientContext.Web.GetFileByServerRelativeUrl("/" + vURL);
                clientContext.Load(oldFile);
                clientContext.Load(oldFile, item => item.ListItemAllFields);
                ClientResult<System.IO.Stream> data = oldFile.OpenBinaryStream();
                clientContext.ExecuteQuery();

                using (System.IO.MemoryStream mStream = new System.IO.MemoryStream())
                {
                    if (data != null)
                    {
                        data.Value.CopyTo(mStream);
                        fileBytes = mStream.ToArray();
                    }
                }
            }
        }
    }
}

Answer 1

我们可以使用以下代码从SharePoint Online使用CSOM（C＃）下载文件版本。

string _SharePointSiteURL = @"https://lz.sharepoint.com/sites/lz";

var _SharePointSiteUser = "lz@lz.onmicrosoft.com";
var password = "Password";

var securePassword = new SecureString();

foreach (char c in password)
{
    securePassword.AppendChar(c);
}

using (var clientContext = new ClientContext(_SharePointSiteURL))
{
    var onlineCredentials = new SharePointOnlineCredentials(_SharePointSiteUser, securePassword);
    clientContext.RequestTimeout = 10000000;
    clientContext.Credentials = onlineCredentials;
    Web web = clientContext.Web;
    clientContext.Load(web, website => website.ServerRelativeUrl, website => website.Url);
    clientContext.ExecuteQuery();

    var spFile = clientContext.Web.GetFileByServerRelativeUrl((web.ServerRelativeUrl.EndsWith("/") ? web.ServerRelativeUrl : web.ServerRelativeUrl + "/") + "Shared Documents/ABC/Test.pdf");
    clientContext.Load(spFile);
    FileVersionCollection versions = spFile.Versions;
    clientContext.Load(versions);
    var oldVersions = clientContext.LoadQuery(versions.Where(v => v != null));
    clientContext.ExecuteQuery();
    if (oldVersions != null)
    {
        foreach (Microsoft.SharePoint.Client.FileVersion _version in oldVersions)
        {
            if (_version.VersionLabel == "2.0")
            {
                var localPath = @"c:\test\";
                if (!Directory.Exists(localPath))
                {
                    Directory.CreateDirectory(localPath);
                }

                using (var wc = new System.Net.WebClient())
                {                       
                    wc.Credentials = onlineCredentials;
                    wc.Headers.Add("X-FORMS_BASED_AUTH_ACCEPTED", "f");
                    wc.Headers["User-Agent"] = "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; WOW64; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; MDDC)";
                    wc.DownloadFile(web.Url + "/" + _version.Url, localPath+"Test.pdf");
                }                  
            }
        }
    }
}

Answer 2

试试这段代码：

var onlineCredentials = new SharePointOnlineCredentials(_SharePointSiteUser, securePassword);
clientContext.RequestTimeout = 10000000;
clientContext.Credentials = onlineCredentials; 
Microsoft.SharePoint.Client.File file = clientContext.Web.GetFileByServerRelativeUrl(_SharePointSiteURL + "/Shared Documents/ABC/Test.pdf");
FileVersionCollection fileVersions = file.Versions; 
clientContext.Load(file); 
clientContext.Load(fileVersions);
clientContext.ExecuteQuery();

// Download all versions of specific file as individual docs
int index = 0;
foreach (var version in fileVersions)
{
    if (version.VersionLabel == "2.0")
    {
       var str = version.OpenBinaryStream();
       clientContext.ExecuteQuery();

       string filename = string.Format("d:\\downloaded\\doc-{0}.docx", index);
       using (var fs = new FileStream(filename, FileMode.OpenOrCreate))
       {
         str.Value.CopyTo(fs);
       }
       index++;
    }
}

确保您使用的是最新版本的CSOM或更改2017年9月更新后的版本。

建议您使用Nuget获取最新的SharePoint在线csom包。

参考 - SPO CSOM September 2017

使用Micrsoft.SharePoint.Client下载共享点版本文件

2 个答案: