SharePoint 2010 - 客户端对象模型 - 向ListItem添加附件

Question

我有一个SharePoint列表,我正在使用客户端对象模型添加新的ListItems.添加ListItems不是问题,效果很好.

现在我想添加附件.

我以下列方式使用SaveBinaryDirect:

File.SaveBinaryDirect(clientCtx, url.AbsolutePath + "/Attachments/31/" + fileName, inputStream, true);

只要我尝试添加附件的项目已经具有通过SharePoint网站添加的附件而不使用客户端对象模型,它就没有任何问题.

当我尝试将附件添加到没有任何附件的项目时,我会收到以下错误(两者都发生但没有相同的文件 - 但这两个消息始终显示):

The remote server returned an error: (409) Conflict

The remote server returned an error: (404) Not Found

我想我可能需要先为这个项目创建附件文件夹.当我尝试以下代码时:

clientCtx.Load(ticketList.RootFolder.Folders);
clientCtx.ExecuteQuery();
clientCtx.Load(ticketList.RootFolder.Folders[1]);             // 1 -> Attachment folder
clientCtx.Load(ticketList.RootFolder.Folders[1].Folders);
clientCtx.ExecuteQuery();
Folder folder = ticketList.RootFolder.Folders[1].Folders.Add("33");
clientCtx.ExecuteQuery();

我收到一条错误消息:

Cannot create folder "Lists/Ticket System/Attachment/33"

我拥有SharePoint站点/列表的完全管理员权限.

我有什么想法可能做错了吗？

谢谢,Thorben

Answer 1

我也在这个问题上挣扎了很长时间,所以我想我会发布一个完整的代码示例,展示如何成功创建列表项并添加附件.

我使用Client Object API创建列表项,使用SOAP Web服务添加附件.这是因为,如在Web上的其他位置所述,客户端对象API仅可用于向项目的上载目录已存在的项目添加附件(例如,如果项目已经具有附件).否则它会因409错误而失败.SOAP Web服务虽然可以解决这个问题.

请注意,我必须克服的另一件事是,即使我使用以下URL添加了SOAP引用:

HTTPS://my.sharepoint.installation/personal/test/_vti_bin/lists.asmx

VS实际添加到app.config的URL是:

HTTPS://my.sharepoint.installation/_vti_bin/lists.asmx

我不得不手动将app.config更改回正确的URL,否则我会收到错误:

列表不存在.您选择的页面包含一个不存在的列表.它可能已被其他用户删除.0x82000006

这是代码:

    void CreateWithAttachment()
    {
        const string listName = "MyListName";
        // set up our credentials
        var credentials = new NetworkCredential("username", "password", "domain");

        // create a soap client
        var soapClient = new ListsService.Lists();
        soapClient.Credentials = credentials;

        // create a client context
        var clientContext = new Microsoft.SharePoint.Client.ClientContext("https://my.sharepoint.installation/personal/test");
        clientContext.Credentials = credentials;

        // create a list item
        var list = clientContext.Web.Lists.GetByTitle(listName);
        var itemCreateInfo = new ListItemCreationInformation();
        var newItem = list.AddItem(itemCreateInfo);

        // set its properties
        newItem["Title"] = "Created from Client API";
        newItem["Status"] = "New";
        newItem["_Comments"] = "here are some comments!!";

        // commit it
        newItem.Update();
        clientContext.ExecuteQuery();

        // load back the created item so its ID field is available for use below
        clientContext.Load(newItem);
        clientContext.ExecuteQuery();

        // use the soap client to add the attachment
        const string path = @"c:\temp\test.txt";
        soapClient.AddAttachment(listName, newItem["ID"].ToString(), Path.GetFileName(path),
                                  System.IO.File.ReadAllBytes(path));
    }

希望这有助于某人.

Answer 2

我和微软讨论了这个问题.看起来只有一种远程创建附件的方法是List.asmx Web服务.我也试图创建这个子文件夹,但没有成功.

Answer 3

使用Sharepoint 2010,无法使用COM将第一个附件上载到列表项.建议是使用列表Web服务.

使用Sharepoint 2013,它可以正常运行.

AttachmentCreationInformation newAtt = new AttachmentCreationInformation();
newAtt.FileName = "myAttachment.txt";
// create a file stream
string fileContent = "This file is was ubloaded by client object meodel ";
System.Text.ASCIIEncoding enc = new System.Text.ASCIIEncoding();
byte[] buffer = enc.GetBytes(fileContent);
newAtt.ContentStream = new MemoryStream(buffer);

// att new item or get existing one
ListItem itm = list.GetItemById(itemId);
ctx.Load(itm);   
// do not execute query, otherwise a "version conflict" exception is rised, but the file         is uploaded
// add file to attachment collection
newAtt.ContentStream = new MemoryStream(buffer);
itm.AttachmentFiles.Add(newAtt); 
AttachmentCollection attachments = itm.AttachmentFiles;
ctx.Load(attachments);
ctx.ExecuteQuery(); 
// see all attachments for list item
// this snippet works if the list item has no attachments

此方法用于http://www.mailtosharepoint.net/