vb.net client object model: get wikipagelibrarytitle/list by url

Question

I am using the .net client object model for SharePoint 2010. I am able to create a new wiki page in my wikipagelibrary using the following method:

    Dim wikiLibrary = context.Web.Lists.GetByTitle(wikiPageLibraryTitle)
    context.Load(wikiLibrary.RootFolder)
    context.ExecuteQuery()

    Dim relativeUrl As String = "/sites/kdb/" & txt.Text & "/" & pageName
    Dim fileAlreadyExcists As Boolean = CheckIfWikiPageExcists(context, relativeUrl)

    If Not fileAlreadyExcists Then
        Dim pageUrl = String.Format("{0}/{1}", wikiLibrary.RootFolder.ServerRelativeUrl, pageName)
        Dim wikiFile = wikiLibrary.RootFolder.Files.AddTemplateFile(pageUrl, TemplateFileType.WikiPage)
        context.Load(wikiFile)
        context.ExecuteQuery()

        Dim wikiPage = wikiFile.ListItemAllFields
        wikiPage("WikiField") = pageContent
        wikiPage.Update()
        context.ExecuteQuery()
    Else
        MessageBox.Show("Deze Pagina bestaat al!")
    End If

One of the parameters of this method is "wikiPageLibraryTitle". How can I get that title if i only know the URL of the library?

Answer 1

There is no built-in method for retrieving List by its Url, in C# CSOM the following method could be used for that purpose:

public static List LoadListByUrl(ClientContext context,string listUrl)
{
   var lists = context.LoadQuery(context.Web.Lists.Where(l => l.RootFolder.ServerRelativeUrl == listUrl));
   context.ExecuteQuery();
   return lists.FirstOrDefault();
}

Unfortunately the specified method could not be directly converted into VB.NET CSOM due to the limitation with LINQ expressions in VB.NET, for example, the following function:

Public Function GetListByUrl(ByVal context As ClientContext, ByVal listUrl As String) As List
    Dim query = context.LoadQuery( _
                context.Web.Lists.Where(Function(l) l.RootFolder.ServerRelativeUrl = listUrl))
    context.ExecuteQuery()
    Return query.FirstOrDefault()
End Function

will return Microsoft.SharePoint.Client.ClientRequestException exception.

---

Solution

But, you could use the following function to load List by its Url:

Public Function LoadListByUrl(ByVal context As ClientContext, ByVal listUrl As String) As List
    context.Load(context.Web.Lists, Function(lcol) lcol.Include(Function(l) l.RootFolder))
    context.ExecuteQuery()
    Return context.Web.Lists.SingleOrDefault(Function(l) l.RootFolder.ServerRelativeUrl = listUrl)
End Function

Usage

Load Pages list located on news web site:

Dim listUrl = "/news/Pages"
Dim list = LoadListByUrl(ctx, listUrl)