How To: Get a list of Outlook contacts

A while ago I described two ways of getting Outlook contact items from a folder: by using the Find/FindNext and Restrict methods of the Items class. Today I am going to show how you can get a list of all contacts of a certain Outlook user. As a rule, there are two folders containing contact items: Contacts and Suggested Contacts folders. You can get the Contacts folder using the GetDefaultFolder method of the Namespace class. The olFolderContacts constant of the OlDefaultFolders enumeration should be used for this task. But how can we get the Suggested Contacts folder?

Outlook 2010 introduced new constants in the OlDefaultFolders enumeration, which can be passed to the GetDefaultFolder method of the Namespace class. One of them is olFolderSuggestedContacts. As you may guess, it allows you to retrieve the Suggested Contacts folder in Outlook. This folder contains one-off entries that are used in pop-up prompts to finish the sentence when you enter an e-mail address in one of the recipient fields (TO, CC, BCC).

The code shown below collects all contact items from the two mentioned folders using the for loop. The function accepts an instance of the Application class from the Oultook Object Model and returns an instance of the generic List collection which contains contact items. Please remember that all underlying COM objects should be released later!

C# and Add-in Express:

using System.Collections.Generic;
// ...
private List<Outlook.ContactItem> GetListOfContacts(Outlook._Application OutlookApp)
{
    List<Outlook.ContactItem> contactItemsList = null;
    Outlook.Items folderItems =null;
    Outlook.MAPIFolder folderSuggestedContacts = null;
    Outlook.NameSpace ns = null;
    Outlook.MAPIFolder folderContacts = null;
    object itemObj = null;
    try
    {
        contactItemsList = new List<Outlook.ContactItem>();
        ns = OutlookApp.GetNamespace("MAPI");
        // getting items from the Contacts folder in Outlook
        folderContacts = ns.GetDefaultFolder(Outlook.OlDefaultFolders.olFolderContacts);
        folderItems = folderContacts.Items;
        for (int i = 1; folderItems.Count >= i; i++)
        {
            itemObj = folderItems[i];
            if (itemObj is Outlook.ContactItem)
                contactItemsList.Add(itemObj as Outlook.ContactItem);
            else
                Marshal.ReleaseComObject(itemObj);
        }
        Marshal.ReleaseComObject(folderItems);
        folderItems = null;
        // getting items from the Suggested Contacts folder in Outlook
        folderSuggestedContacts = ns.GetDefaultFolder(
                                  Outlook.OlDefaultFolders.olFolderSuggestedContacts);
        folderItems = folderSuggestedContacts.Items;
        for (int i = 1; folderItems.Count >= i; i++)
        {
            itemObj = folderItems[i];
            if (itemObj is Outlook.ContactItem)
                contactItemsList.Add(itemObj as Outlook.ContactItem);
            else
                Marshal.ReleaseComObject(itemObj);
        }
    }
    catch (Exception ex)
    {
        System.Windows.Forms.MessageBox.Show(ex.Message);
    }
    finally
    {
        if (folderItems != null) 
            Marshal.ReleaseComObject(folderItems);
        if (folderContacts != null) 
            Marshal.ReleaseComObject(folderContacts);
        if (folderSuggestedContacts != null) 
            Marshal.ReleaseComObject(folderSuggestedContacts);
        if (ns != null) Marshal.ReleaseComObject(ns);
    }
    return contactItemsList;
}

VB.NET and Add-in Express:

Imports System.Collections.Generic
' ...
Private Function GetListOfContacts(OutlookApp As Outlook._Application) _
                                       As List(Of Outlook.ContactItem)
    Dim contactItemsList As List(Of Outlook.ContactItem) = Nothing
    Dim folderItems As Outlook.Items = Nothing
    Dim folderSuggestedContacts As Outlook.MAPIFolder = Nothing
    Dim ns As Outlook.NameSpace = Nothing
    Dim folderContacts As Outlook.MAPIFolder = Nothing
    Dim itemObj As Object = Nothing
    Try
        contactItemsList = New List(Of Outlook.ContactItem)()
        ns = OutlookApp.GetNamespace("MAPI")
        ' getting items from the Contacts folder in Outlook
        folderContacts = ns.GetDefaultFolder(Outlook.OlDefaultFolders.olFolderContacts)
        folderItems = folderContacts.Items
        For i As Integer = 1 To folderItems.Count
            itemObj = folderItems(i)
            If (TypeOf (itemObj) Is Outlook.ContactItem) Then
                contactItemsList.Add(itemObj)
            Else
                Marshal.ReleaseComObject(itemObj)
            End If
        Next
        Marshal.ReleaseComObject(folderItems)
        folderItems = Nothing
        ' getting items from the Suggested Contacts folder in Outlook
        folderSuggestedContacts = ns.GetDefaultFolder( _
                                  Outlook.OlDefaultFolders.olFolderSuggestedContacts)
        folderItems = folderSuggestedContacts.Items
        For i As Integer = 1 To folderItems.Count
            itemObj = folderItems(i)
            If (TypeOf (itemObj) Is Outlook.ContactItem) Then
                contactItemsList.Add(itemObj)
            Else
                Marshal.ReleaseComObject(itemObj)
            End If
        Next
    Catch ex As Exception
        System.Windows.Forms.MessageBox.Show(ex.Message)
    Finally
        If Not IsNothing(folderItems) Then 
            Marshal.ReleaseComObject(folderItems)
        End If
        If Not IsNothing(folderContacts) Then 
            Marshal.ReleaseComObject(folderContacts)
        End If
        If Not IsNothing(folderSuggestedContacts) Then 
            Marshal.ReleaseComObject(folderSuggestedContacts)
        End If
        If Not IsNothing(ns) Then 
            Marshal.ReleaseComObject(ns)
        End If
    End Try
    Return contactItemsList
End Function

C# and VSTO:

using System.Runtime.InteropServices;
// ...
private List<Outlook.ContactItem> GetListOfContacts(Outlook._Application Application)
{
    List<Outlook.ContactItem> contactItemsList = null;
    Outlook.Items folderItems = null;
    Outlook.MAPIFolder folderSuggestedContacts = null;
    Outlook.NameSpace ns = null;
    Outlook.MAPIFolder folderContacts = null;
    object itemObj = null;
    try
    {
        contactItemsList = new List<Outlook.ContactItem>();
        ns = Application.GetNamespace("MAPI");
        // getting items from the Contacts folder in Outlook
        folderContacts = ns.GetDefaultFolder(Outlook.OlDefaultFolders.olFolderContacts);
        folderItems = folderContacts.Items;
        for (int i = 1; folderItems.Count >= i; i++)
        {
            itemObj = folderItems[i];
            if (itemObj is Outlook.ContactItem)
                contactItemsList.Add(itemObj as Outlook.ContactItem);
            else
                Marshal.ReleaseComObject(itemObj);
        }
        Marshal.ReleaseComObject(folderItems);
        folderItems = null;
        // getting items from the Suggested Contacts folder in Outlook
        folderSuggestedContacts = ns.GetDefaultFolder(
                                  Outlook.OlDefaultFolders.olFolderSuggestedContacts);
        folderItems = folderSuggestedContacts.Items;
        for (int i = 1; folderItems.Count >= i; i++)
        {
            itemObj = folderItems[i];
            if (itemObj is Outlook.ContactItem)
                contactItemsList.Add(itemObj as Outlook.ContactItem);
            else
                Marshal.ReleaseComObject(itemObj);
        }   
    }
    catch (Exception ex)
    {
        System.Windows.Forms.MessageBox.Show(ex.Message);
    }
    finally
    {
        if (folderItems != null) 
            Marshal.ReleaseComObject(folderItems);
        if (folderContacts != null) 
            Marshal.ReleaseComObject(folderContacts);
        if (folderSuggestedContacts != null) 
            Marshal.ReleaseComObject(folderSuggestedContacts);
        if (ns != null) 
            Marshal.ReleaseComObject(ns);
    }
    return contactItemsList;
}

VB.NET and VSTO:

Imports System.Runtime.InteropServices
' ...
Private Function GetListOfContacts(OutlookApp As Outlook._Application) _
                                       As List(Of Outlook.ContactItem)
    Dim contactItemsList As List(Of Outlook.ContactItem) = Nothing
    Dim folderItems As Outlook.Items = Nothing
    Dim folderSuggestedContacts As Outlook.MAPIFolder = Nothing
    Dim ns As Outlook.NameSpace = Nothing
    Dim folderContacts As Outlook.MAPIFolder = Nothing
    Dim itemObj As Object = Nothing
    Try
        contactItemsList = New List(Of Outlook.ContactItem)()
        ns = OutlookApp.GetNamespace("MAPI")
        ' getting items from the Contacts folder in Outlook
        folderContacts = ns.GetDefaultFolder(Outlook.OlDefaultFolders.olFolderContacts)
        folderItems = folderContacts.Items
        For i As Integer = 1 To folderItems.Count
            itemObj = folderItems(i)
            If (TypeOf (itemObj) Is Outlook.ContactItem) Then
                contactItemsList.Add(itemObj)
            Else
                Marshal.ReleaseComObject(itemObj)
            End If
        Next
        Marshal.ReleaseComObject(folderItems)
        folderItems = Nothing
        ' getting items from the Suggested Contacts folder in Outlook
        folderSuggestedContacts = ns.GetDefaultFolder( _
                                  Outlook.OlDefaultFolders.olFolderSuggestedContacts)
        folderItems = folderSuggestedContacts.Items
        For i As Integer = 1 To folderItems.Count
            itemObj = folderItems(i)
            If (TypeOf (itemObj) Is Outlook.ContactItem) Then
                contactItemsList.Add(itemObj)
            Else
                Marshal.ReleaseComObject(itemObj)
            End If
        Next
    Catch ex As Exception
        System.Windows.Forms.MessageBox.Show(ex.Message)
    Finally
        If Not IsNothing(folderItems) Then 
            Marshal.ReleaseComObject(folderItems)
        End If
        If Not IsNothing(folderContacts) Then 
            Marshal.ReleaseComObject(folderContacts)
        End If
        If Not IsNothing(folderSuggestedContacts) Then 
            Marshal.ReleaseComObject(folderSuggestedContacts)
        End If
        If Not IsNothing(ns) Then 
            Marshal.ReleaseComObject(ns)
        End If
    End Try
    Return contactItemsList
End Function

To get more information about the methods and properties provided by the Outlook Object Model, please use the Object Browser in the VBA environment.

See you on our forums and in the support e-mail address!