Question

My Task have multiple relateddocId for example RelatedDoc=”3,5,2,6″, now i need to add multiplevalue to the sharepoint lookup fields called related Document which is in task list. how to add this?

For ref see my code below

   private static void CreateItem(SPWeb web, SPList TaskList, string FolderURL, string ItemName, string RelatedDoc)
    {
        var ParentURL = string.Empty;
        if (!TaskList.ParentWebUrl.Equals("/"))
        {
            ParentURL = TaskList.ParentWebUrl;
        }
        SPListItem _taskList = TaskList.AddItem(ParentURL + FolderURL, SPFileSystemObjectType.File, null);
        _taskList["Title"] = ItemName;
        string DocName = "4,6,3,6";//Document ref id.
        SPFieldLookupValue lookupvalue = new SPFieldLookupValue();

        if (DocName != "")
            lookupvalue = new SPFieldLookupValue(RelatedDoc, DocName);
        _taskList["EYRelatedSharedDocument"] = lookupvalue;
        _taskList.Update();

    }

Answer 1

SPFieldLookupValueCollection documents = new SPFieldLookupValueCollection();

foreach ( ... )
{
    documents.Add(new SPFieldLookupValue(documentId, documentTitle));
}

_taskList["EYRelatedSharedDocument"] = documents;
_taskList.Update();