Setting the Search Scope

To increase search performance, limit the search scope search to a single object or subset of objects. For this task, DirectorySearcher provides the SearchScope property.

The search scope can be set to one of the three following settings:

• Base. Searches the bound object and return only that object if it matches the search criterion. For example, if you are bound to the ___domain, then it will search everything in that ___domain and return only the bound object.
• OneLevel. Searches all objects that are contained in the same level as the bound object. For example, if you are bound to a group, it will search all groups or other objects that are at the same level as that group.
• Subtree. Searches all objects that are contained in the sub-tree of the bound object, including the base object. For example, if you are bound to a server, it will search all objects in the hierarchy that are on the same level or under that server. This is the default value. If you perform a directory synchronization search with a DirectorySynchronization object, the application is required to specify Subtree scope.

The following illustration shows how each of these scopes fits within your ___domain hierarchy.

The following C# code example shows how to use the SearchScope property to search a sub-tree.

DirectoryEntry entry = new DirectoryEntry("LDAP://CN=users,DC=fabrikam,DC=com");
DirectorySearcher mySearcher = new DirectorySearcher(entry);
mySearcher.SearchScope = SearchScope.Subtree;
mySearcher.Filter = "(&(objectClass=user)(anr=test*))";
SearchResultCollection ResEnt = mySearcher.FindAll();
{
    // Handle results.
}
// Handle exceptions.

See Also

Reference

System.DirectoryServices
DirectorySearcher
SearchScope
DirectorySynchronization

Concepts

Searching the Directory

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