get guid of a listitem - sharepoint

Question

I have text file with List Name and item name. I need to get item guid by it's name. how? (not using foreach splistitem item in splist cause the text file is large and the loop is going to take a toll)

Answer 1

You may have enough information to use the SPWeb function GetListItem, otherwise you will need to try SPWeb.SearchListItems. Neither of which is going to be all the fast either.
The web services have a decent search function that I have used such as:
public static string GetPageId(string listName, string webPath, string pageTitle)
{
string pageId = "";
IntranetLists.Lists lists = new IntranetLists.Lists();
lists.UseDefaultCredentials = true;
lists.Url = webPath + "/_vti_bin/lists.asmx";
XmlDocument doc = new XmlDocument();
doc.LoadXml("<Document><Query><Where><Contains><FieldRef Name=\"Title\" /><Value Type=\"Text\">" + pageTitle + "</Value></Contains></Where></Query><ViewFields /><QueryOptions /></Document>");
XmlNode listQuery = doc.SelectSingleNode("//Query");
XmlNode listViewFields = doc.SelectSingleNode("//ViewFields");
XmlNode listQueryOptions = doc.SelectSingleNode("//QueryOptions");
Guid g = GetWebID(webPath);
XmlNode items = lists.GetListItems(listName, string.Empty, listQuery, listViewFields, string.Empty, listQueryOptions, g.ToString());
foreach (XmlNode listItem in SPCollection.XpathQuery(items, "//sp:listitems/rs:data/z:row"))
{
XmlAttribute id = listItem.Attributes["ows_Id"];
if (id != null)
{
pageId = id.Value;
}
}
return pageId;
}
public static XmlNodeList XpathQuery(XmlNode xmlToQuery, string xPathQuery)
{
XmlDocument doc = new XmlDocument();
doc.LoadXml(xmlToQuery.OuterXml);
XmlNamespaceManager mg = new XmlNamespaceManager(doc.NameTable);
mg.AddNamespace("sp", "http://schemas.microsoft.com/sharepoint/soap/");
mg.AddNamespace("z", "#RowsetSchema");
mg.AddNamespace("rs", "urn:schemas-microsoft-com:rowset");
mg.AddNamespace("y", "http://schemas.microsoft.com/sharepoint/soap/ois");
mg.AddNamespace("w", "http://schemas.microsoft.com/WebPart/v2");
mg.AddNamespace("d", "http://schemas.microsoft.com/sharepoint/soap/directory");
return doc.SelectNodes(xPathQuery, mg);
}

Answer 2

http://msdn.microsoft.com/en-us/library/microsoft.sharepoint.spsitedataquery.aspx or CamlQuery
SPListItemCollection items = web.Lists.GetItems(new SPQuery() { Query = "YOUR QUERY" });

Answer 3

Go to the list settings page. Right click on "Title, description and navigation" and copy the URL. Paste that into notepad and copy everything after "List=" in the string. That's your URL Encoded GUID for the list. All you need to do is decode it here http://www.albionresearch.com/misc/urlencode.php
source: http://weblogs.asp.net/jimjackson/archive/2008/02/11/get-a-sharepoint-list-guid-from-the-browser.aspx
this is for manually getting each GUID of a certain list.