Tài liệu Module 11: Accessing Data from the Outlook 2000 Client ppt

Updating Data in an ADO Data Source 28 Accessing Exchange Server Information 37 Lab A: Searching and Retrieving Information in the Exchange Server Directory by Using ADSI 54 Review 5

Updating Data in an ADO Data Source 28

Accessing Exchange Server Information 37

Lab A: Searching and Retrieving

Information in the Exchange Server

Directory by Using ADSI 54

Review 57

Module 11: Accessing Data from the

Outlook 2000 Client

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Project Lead and Instructional Designer: Anne Bockman (Excell Data Corporation)

Instructional Designers: Josh Barnhill (Volt Technical) and Jo Berry (Exchange)

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Group Product Manager: Robert Stewart

Instructor Notes Module 11: Accessing Data from the

in the Microsoft Exchange Server directory by using the Outlook object model, Collaborative Data Objects (CDO), and Microsoft Active Directory™ Service

Interfaces (ADSI)

Materials and Preparation

This section provides you with the materials and preparation needed to teach this module

Materials

To teach this module, you need the following materials:

Microsoft PowerPoint® file 1593a_11.ppt

Module 11, “Accessing Data from the Outlook 2000 Client”

Preparation

To prepare for this module, you should:

Read all the materials for this module

Read the instructor notes and margin notes for the module

Complete the lab

Rehearse the demonstration

Presentation:

60 Minutes

Lab:

45 Minutes

Module Strategy

Use the following strategy to present this module:

Introduction to Data Access in Outlook 2000 Solutions Describe the different ways that SQL Server data and Exchange directory information can be accessed from the Outlook 2000 client

Using Office Web Components Define the Office Web components Show how to create a Web page that uses the Microsoft Excel PivotTable® List control and Microsoft Access data access pages

Using ADO Provide an overview of OLE DB and describe its architecture Then, explain where ADO fits in this architecture Provide a high-level discussion of the main objects in the ADO object model Define an ADO recordset and describe how it is used

Retrieving Data from an ADO Data Source Describe the steps required to connect to a data source and return a

Recordset object Once students have learned how to return a recordset,

show some ways that they can work with it Show how to reference fields in

a recordset, explain how to use the Move methods to navigate through the records in a recordset, and how to use filtering to show only those records

that meet a specified criteria Finally, explain how to use the Command

object to execute a stored procedure

Updating Data in an ADO Data Source Describe two ways to update data in an ADO data source: by using the

Execute method of the Command and Connection objects, and by using a

recordset

Accessing Exchange Server Directory Information Describe the purpose of the Exchange Server directory and the different ways that developers can access the information that is stored there Discuss the objects in the Outlook object model that enable developers to access address book information Introduce CDO as another way to retrieve address book information Provide a definition of the Active Directory Service Interfaces (ADSI) and its provider-based model Explain how to view the directory schema and why this is important to developing ADSI applications Use the objects provided by ADSI to search the directory and update its contents

Overview

Introduction to Data Access in Outlook 2000 Solutions

Using Office Web Components

Using ADO

Retrieving Data from an ADO Data Source

Updating Data in an ADO Data Source

Accessing Exchange Server Information

At the end of this module, you will be able to:

Describe the different ways that data can be accessed from the Microsoft® Outlook® 2000 client

Add a Microsoft Office Web component that connects to an external data source to a Web page

Define the relationship between Microsoft ActiveX® Data Objects (ADO) and OLE DB

Use ADO to connect to a data source, such as a Microsoft SQL Server™database, and retrieve data from that data source

Use ADO to add a new record to a data source

Define how Microsoft Active Directory™ Service Interfaces (ADSI), the directory access functions, and the Collaboration Data Objects (CDO) library can be used to access the Microsoft Exchange Server directory

In this module, you will learn

how to gain access to

various types of data from

your Outlook 2000 solutions

Introduction to Data Access in Outlook 2000 Solutions

Using SQL Server Data from Outlook 2000

Microsoft Visual Basic or Visual Basic for Applications and ADO in Outlook 2000

Using the Exchange Server Directory from Outlook 2000

Using SQL Server Data from Outlook 2000

Two ways you can incorporate SQL Server data into your Outlook 2000 solution include:

Office Web Components and Data Access Pages Microsoft Office Web

components are Component Object Model (COM) controls that you can use

to publish interactive spreadsheets, charts, Microsoft PivotTable® lists, and databases for the Web Data access pages are interactive Web pages that maintain a live link to a host Access or SQL Server database With this live link, users can view, edit, and manipulate data within a browser window These components can be placed in a folder home page or an Outlook 2000 form to provide quick access to SQL Server data

Microsoft Visual Basic® or Visual Basic for Applications and ADO in Outlook 2000 Within Outlook 2000, you can use ADO from Microsoft

Visual Basic, Scripting Edition (VBScript), Visual Basic for Applications,

or a COM add-in You can use ADO to view, manipulate, add, or delete records in a SQL Server database

There are several ways that

you can use client-side data

access from the

Outlook 2000 client to SQL

Server and Exchange

Server directory data

sources

Using the Exchange Server Directory from Outlook 2000

The Exchange Server directory contains information that you can use in your Outlook 2000 solutions For example, you can use the objects contained in the directory to set up mailboxes or to obtain information about mail recipients Several ways that you can access Exchange Server directory data from Outlook 2000 include:

Outlook Object Model The Outlook object model provides objects that you

can use to gain read-only access the Exchange Server address book

CDO The CDO Library is an interface to MAPI that provides an easy

method for gaining access to the directory information stored within an

Exchange Server Global Address List (GAL)

ADSI ADSI is a set of specifications of COM objects and interfaces that

you can use to manipulate Exchange Server directory services and other directory services You can use the ADSI objects to perform common administrative operations, such as adding new users or managing a print

queue

Using Office Web Components

Introduction to Office Web Components

Publishing an Interactive Web Page from Excel

Using Data Access Pages

Using the Data Source Control

The Office Web components are COM controls that you can use to publish interactive spreadsheets, charts, PivotTable lists, and databases for the Web Office Web components provide a way to quickly add data access capabilities

to Outlook 2000 client applications You can base these components on an external data source, such as a SQL Server database, and then add them to Outlook 2000 forms or to folder home pages

Slide Objective

To outline this topic

Lead-in

Office Web components

provide a way to quickly add

data access capabilities to

client side applications

Introduction to Office Web Components

Using Office Web Components in a Solution

Create a worksheet, PivotTable, or chart in Excel

Library

Capabilities of Office Web Components

Office Web components enable you to incorporate spreadsheets, PivotTable lists, charts, and data access pages into a solution in a number of different ways

Using Office Web Components in a Solution

You can use the Web components in your Outlook 2000 solution in the following ways:

Create a worksheet, PivotTable, or chart in Excel, and then save your work

as an interactive folder home page

Create a data access page in Access and save it as an interactive folder home page

Add a reference to the Microsoft Office Web Components Object Library to your custom application by using any development environment that supports COM; then use the components as you would any other COM object through automation

Use the Office Web components in Active Server Pages (ASP), and then generate static Hypertext Markup Language (HTML) or interactive Web pages for display on the Internet or intranet client

With Web components, users can interact with a Web page from within a browser, while using many of the features that are found in the full version of the application

Slide Objective

To describe the different

ways that Office Web

components can be used in

a solution and to list the

different components that

are available

Lead-in

Office Web components are

implemented as COM

controls, so they can be

used from Web pages or

any other development

environment that supports

COM

Capabilities of Office Web Components

The following table lists and describes the capabilities of each component

Component Description

Spreadsheet Provides a recalculation engine, a full function library, and a

simple spreadsheet user interface A spreadsheet is created when a worksheet is saved with interactivity

PivotTable List Provides sorting, grouping, filtering, outlining, and pivoting

capabilities A PivotTable can connect to data from a spreadsheet range, a relational database, or a multidimensional database It can

be generated by Excel from a PivotTable object or designed with the Data Access Pages Designer in Access

Data Source The reporting engine behind data access pages and the PivotTable

component The data source component manages data access with the database servers by, for example, retrieving records and managing the sorting, filtering, and updating of records

Chart Graphically displays information from a spreadsheet, a

PivotTable, or the data source component A chart updates instantly in response to user interaction with the other components

Users must have Microsoft Internet Explorer version 4.01 (or later) and

an Office 2000 license to browse a Web page interactively by using Office Web components

Note

Publishing an Interactive Web Page from Excel

C:\My Documents\Page.htm – Microsoft Internet Explorer provided by ITG

File Edit View Go Favorites Help

Links Address C:\My Documents\Page.htm

42 32 40 114

33 20 18 71

20 50 70

95 102 58 255 Sum of Quantity Sum of Quantity Sum of Quantity Sum of Quantity

My Computer

You create an interactive Web page from Excel by first creating the

spreadsheet, PivotTable, or chart and then clicking Save As Web Page on the

File menu

To publish an interactive Web page from Excel:

1 Activate the worksheet that contains the worksheet, PivotTable, or chart

2 On the File menu, click Save as Web Page

3 Click Publish

4 In the Choose list, select the type of data that you want to publish In the list

box, click the item that you want

5 Select the Add interactivity with check box, and then choose the type of

functionality (Spreadsheet, PivotTable, or Chart)

6 To add a title to the published section, click Change, enter the title that you want, and then click OK

7 Click the Browse button, and locate the drive, folder, Web folder, Web

server, or File Transfer Protocol (FTP) location where you want to publish your Web page

8 Click Publish

Slide Objective

To show a Web page that

uses Office Web

components

Lead-in

You create a Web page that

uses Office Web

components by first creating

the spreadsheet,

PivotTable, or chart in

Excel

Using Data Access Pages

Category Entry Page – Microsoft Internet Explorer provided by ITG

File Edit View Go Favorites Help

Links Address C:\My Documents\Category Entry Page.htm

Description

Beverages Soft drinks, coffees, teas, beers, and ales

Categories 1 of 8

Done

Data access pages are interactive Web pages that maintain a live link to a host Access or SQL Server database With this live link, users can view, edit, and manipulate data within a browser window

You can create two types of data access pages—pages that support data entry and pages that are read-only You use the Page Wizard to create both types of data access pages

Slide Objective

To show a data access

page that is based on a SQL

Server database

Lead-in

To maintain a live link to an

Access or SQL Server

database, you must use

data access pages

Creating a Data Entry Page

The Page Wizard makes creating a data entry page simple You specify the table or query that you want to use with the form, and the wizard creates a data input form for you

To create a data entry page by using the Page Wizard:

1 Open your database application

To open an existing SQL Server database in Access:

a On the File menu, click New

b On the Project tab, click Project (Existing Database), and then click

OK

c In the File New Database dialog box, enter a name for the database, and then click Create

d In the Data Link Properties dialog box, provide connection

information for the SQL Server database

e To make the data access page read-only, click the Advanced tab of the

Data Link Properties dialog box, specify access permissions, and then

click OK

The default value for access permissions is Share Deny None, which

means that all users can read and write to the database

2 On the Objects bar, click Pages

3 Double-click Create data access page by using wizard

4 In the Page Wizard dialog box, from the Tables/Queries list, select a table

record-Using the Data Source Control

Function of the Data Source Control

and deliver records

Using the Data Source Control

connection

You can use the Data Source control directly, or indirectly through the use of the other Office Web components

Function of the Data Source Control

The Data Source control is the reporting engine behind data access pages, PivotTable List controls, and data-bound Chart controls The Data Source control has no visual representation at run time It is designed to manage the connection to the underlying data source and deliver records to be displayed by other controls on a Web page

The Data Source control relies on ADO for connections to relational data sources such as Access, SQL Server, or Oracle databases Although the Data Source control can provide data to the PivotTable List control, the Data Source control cannot be bound to multidimensional data sources; transformations of relational data to multidimensional data are managed by the PivotTable Service

Slide Objective

To describe the purpose of

the Data Source control and

how it is used

Lead-in

The Data Source control is

used to perform several

tasks for data access pages,

the PivotTable List control,

and the Chart control

Using the Data Source Control

You can use the Data Source control to do the following:

Associate a DataSourceControl object with a database connection

Add a record (row) source (table, view, stored procedure, or SQL Server statement) to a Data Source control

Provide an ADO recordset to data-consuming objects on a Web page These objects include the Internet Explorer built-in controls that can be data bound, such as the TEXT or SELECT control, and all of the other Office Web Component controls

Build SQL Server commands to request data from relational data sources

Construct hierarchical (shaped) Recordset objects from one or more data

providers by using the services of the Microsoft Data Shaping Service for OLE DB service provider

Persist data in an Office Web component to a file or load data from a file to

an Office Web component

If you are creating a PivotTable list from a relational data source, the PivotTable Service is used to create a multidimensional data cube from the relational data bound to the Data Source control This data cube is then used by the PivotTable List control For multidimensional data sources, the PivotTable List control relies upon an OLE DB for online analytical processing (OLAP) provider The PivotTable Service is the OLE DB for OLAP provider for Microsoft SQL Server OLAP Services

Note

Using ADO

Overview of OLE DB Technology

Using the ADO Object Model

ADO technology is supported by a variety of Microsoft development platforms, including Visual Basic, Visual Basic for Applications, Microsoft Visual Basic, Scripting Edition (VBScript), Microsoft Visual C++®, Microsoft Visual FoxPro®, and Microsoft Visual InterDev®

ADO provides the programmatic interface between OLE DB data and your applications The ADO object model defines a group of objects that allow you

to connect your application to a data source, retrieve and manipulate data from the data source, and disconnect from the data source when you finish using the data

One of the major benefits of ADO is that it requires fewer calls to achieve the same result as earlier data access technologies, such as Remote Data Objects (RDO) Recall that in the Outlook 2000 VBScript environment, all object variables must be declared by using the Variant data type Consequently, these objects use late binding When objects are late bound, a simpler object model results in better performance because there are fewer calls to properties and methods ADO offers the benefits of simplicity without sacrificing

Overview of OLE DB Technology

Data Providers

Database

Visual Basic Application Visual C++ Application

Other Applications ASP Page

Non Relational Data ODBC

OLE DB Provider

ADO provides the interface between Office 2000 applications and OLE DB data OLE DB is Microsoft’s strategic, system-level programming interface to access data throughout an organization Whereas Open Database Connectivity (ODBC) is designed to allow access to relational data, OLE DB is an open standard that is designed to allow access to all kinds of data

Conceptually, OLE DB has three types of components: data providers, data consumers, and service components ADO handles the application-level programming

Data Providers

Data providers are applications (such as SQL Server or Exchange Server), or operating system components (such as a file system) that include data that other applications may need to access These data providers supply the OLE DB interfaces that data consumers or service components can access directly ODBC also has an OLE DB provider that makes ODBC data available to OLE

DB data consumers The examples in this module use SQL Server as the data provider

Data Consumers

Data consumers are applications that use the data exposed by data providers ADO technology provides the programmatic interface for using OLE DB data Any application that uses ADO is an OLE DB data consumer The examples in this module are written by using VBScript, and assume that an Outlook 2000 form is the data consumer

Slide Objective

To show the relationship

between data consumers,

service components, and

data providers in the OLE

or interpretation of SQL Server queries

Advantages of ADO

ADO is a set of high-level Automation interfaces over OLE DB data Although OLE DB is a powerful interface for manipulating data, most application developers do not need the low level of control that OLE DB provides over the data-access process Most collaborative solutions do not need to explicitly manage memory resources, manually aggregate components, and other low-level operations Additionally, developers often use high-level languages that

do not support function pointers and other C++ call mechanisms ADO provides the following advantages to programmers:

Ease of use The data-access task analogous to “Hello World” requires only

three lines of code

Programming language neutral ADO can be used from languages such as

Microsoft Visual Basic, Java, C++, VBScript, and Microsoft JScript®

Provider neutral ADO can access data from any OLE DB source In

addition, ADO adapts gracefully to support less functional OLE DB providers

No loss of OLE DB functionality ADO allows C++ programmers access to

the underlying OLE DB interfaces

Extensible ADO can dynamically expose properties specific to a data

provider by means of collections of provider properties In addition, it provides type extensibility by allowing access to COM objects exposed as column values (for example, rowset and stream)

Using the ADO Object Model

Error (Optional) Field

Parameter (Optional) Recordset

Property (Optional)

Connection

Properties Collection (Optional)

Execute Method Execute Method

Active Connection Property

ADO objects provide you with fast and easy access to all types of data The

ADO object model contains seven objects: Connection, Command,

Recordset, Parameter, Field, Property, and Error It also contains four types

of collections: Fields, Properties, Parameters, and Errors

With ADO, you do not have to navigate through the object hierarchy to create

the objects; you can create all objects independently, except for the Error,

Field, and Property objects Access to the Errors collection and Error object

occurs through the Connection object after a provider error occurs When data exists in the Recordset object, you can access the Fields collection and Field object through the Recordset object The metadata information of the

Recordset object can be viewed through the Fields collection and the Field

object

Main Components of the ADO Object Model

The three main components of the ADO object model are the Connection object, the Command object, and the Recordset object

Connection Object

The Connection object is the highest-level object in the ADO object model It

is used to make a connection between the application and a data source, such as

an Access database or a SQL Server database

Command Object

A Command object is a definition of a specific command that you intend to

execute against a data source, for example, a SQL Server statement or a stored SQL Server procedure

Slide Objective

To show the ADO object

model

Lead-in

The simple ADO object

hierarchy makes it relatively

straightforward to connect to

a data source and use its

data

Recordset Object

By using the Recordset object, you can access the records that a database table

or a SQL Server query return With the Recordset object, you can navigate the

returned records, modify existing records, add new records, or delete specific records

Setting a Reference to ADO

Before you can use the ADO object model in your Visual Basic for Applications code, you need to set a reference to the ADO Object Library

To set the reference to the ADO Object Library:

1 On the Tools menu in the Visual Basic Editor, click References

2 Select Microsoft ActiveX Data Objects 2.1 Library, and then click OK

This step is not necessary if you are using the ADO object model from within an Outlook 2000 form

Retrieving Data from an ADO Data Source

Establishing a Connection

Creating a Recordset Object

Referencing Fields and Data

Navigating Records

Filtering Records

There are two basic steps to retrieving data from a data source with ADO: establish a connection to the data source, and then create a new recordset Once you have created a recordset, you can use its properties and methods to work with its data

Slide Objective

To outline this topic

Lead-in

To retrieve data from a data

source you must complete

two tasks: establish a

connection to the data

source and then create a

new recordset

Establishing a Connection

Declaring a Connection Object

Setting Connection Properties

Opening the Connection

Dim cnNorthwind Set cnNorthwind = _

Item.Application.CreateObject("ADODB.Connection")

Dim cnNorthwind Set cnNorthwind = _

Item.Application.CreateObject("ADODB.Connection")

With cnNorthwind

.Provider = "SQLOLEDB"

.ConnectionString = "User ID=sa;Password=;" & _

"Data Source=MyServer;" & _

"Initial Catalog=Northwind"

End With

With cnNorthwind

.Provider = "SQLOLEDB"

.ConnectionString = "User ID=sa;Password=;" & _

"Data Source=MyServer;" & _

Connection object You specify characteristics of the data source, such as the

data type and location, by setting properties of the Connection object, and then

opening the connection

After you have established a connection to a data source, you can use that connection to create one or more recordsets

Declaring a Connection Object

To establish a connection to the data source, first declare a Connection object

in your application and then create an instance of it

The following code declares and creates an instance of a new Connection

object

Dim cnNorthwind Set cnNorthwind = _ Item.Application.CreateObject("ADODB.Connection")

that data source is the first

step in using ADO

Setting Connection Properties

The Connection object contains information about connections to OLE DB service providers Use the Connection object properties to specify the type of

data source and other information that the OLE DB provider needs to connect

to the data source

Property Description Provider Indicates the name of the OLE DB provider for the connection

The OLE DB provider for SQL Server is specified as

SQLOLEDB

The OLE DB provider for ADSI is specified as ADsDSOObject.

The OLE DB provider for Microsoft Jet 4.0 (for Access

databases) is specified as Microsoft.Jet.OLEDB.4.0

ConnectionString Contains the information that is used to establish a connection to

a data source

SQL Server requires this property but Access does not This information is typically passed to Access when the connection is

opened, rather than by using the ConnectionString property

The following example sets the Provider and ConnectionString properties for

the cnNorthwind connection This code establishes a connection to the SQL Server Northwind database

With cnNorthwind .Provider = "SQLOLEDB"

ConnectionString = "User ID=sa;Password=;" & _ "Data Source=MyServer;" & _

"Initial Catalog=Northwind"

End With

For a complete listing of ADO Connection object properties, search for

“Connection object (ADO)” in Visual Basic Help

Opening the Connection

After you have specified an OLE DB data provider and have passed the

connection information (if required), use the Open method to establish a

connection to the data source

The following example opens the connection to the Northwind SQL Server database

cnNorthwind.Open

Note

Creating a Recordset Object

Creating a Recordset Object

Closing the Recordset and Connection Objects

Dim rsCustomersSet rsCustomers = _Item.Application.CreateObject("ADODB.Recordset")With rsCustomers

.CursorType = adOpenStatic.Open "Customers", cnNorthwindEnd With

Dim rsCustomersSet rsCustomers = _Item.Application.CreateObject("ADODB.Recordset")With rsCustomers

.CursorType = adOpenStatic.Open "Customers", cnNorthwindEnd With

' Close objects and clean uprsCustomers.Close

cnNorthwind.CloseSet rsCustomers = NothingSet cnNorthwind = Nothing

' Close objects and clean uprsCustomers.Close

cnNorthwind.CloseSet rsCustomers = NothingSet cnNorthwind = Nothing

When you use the Recordset object, your application can access data returned from a table or a SQL Server query By using the Recordset object, you can

navigate the records that have been returned, edit their values, add records, or delete records

Creating a Recordset Object

To build a Recordset object that is based on an active connection to a database, first declare and create an instance of a new Recordset object, and then open the Recordset object

Declaring a Recordset Object

The following code declares and creates an instance of a new Recordset object

Dim rsCustomers Set rsCustomers = _ Item.Application.CreateObject("ADODB.Recordset")

In this code example, the Set statement creates a new instance of the recordset

If rsCustomers contains a reference to a different Recordset object, then that

reference will be released when the new one is assigned

Setting Recordset Object Properties

The values that you specify for the CursorType and LockType properties

determine the functionality of the recordset that you created For example, the

constant, adOpenStatic, requests a static type cursor when opening the

recordset A static cursor is a static copy of a set of records that you can use to find data or generate reports Additions, changes, or deletions made by other users after you opened a static copy of the records will not be visible

Slide Objective

To show an example of

creating a Recordset

object, and closing the

Recordset object and

connection objects

Lead-in

Once a connection to a data

source has been

established, you can create

one or more Recordset

objects that are based on

that single connection

The following table lists and describes the properties of the Recordset object

that are commonly used to create a recordset

Property Description CursorType Sets the cursor type The default is adOpenForwardOnly For more

information on CursorType, search for “CursorType property

(ADO)” in Visual Basic Help

LockType Sets the type of record locking The default constant is

adLockReadOnly For more information on LockType, search for

“LockType property (ADO)” in Visual Basic Help

For a complete listing of Recordset object properties, search for

“Recordset object (ADO)” in Visual Basic Help

Opening a Recordset Object

You create a new recordset from an existing Connection object Use the Open method of the Recordset object to open the recordset The Open method opens

a recordset that is based on a particular table or on the result of a SQL Server statement

The following example creates a Recordset object, sets the cursor type to static,

and then opens the Customers table in the Northwind database

Dim rsCustomers Set rsCustomers = _ Item.Application.CreateObject("ADODB.Recordset")

With rsCustomers .CursorType = adOpenStatic .Open "Customers", cnNorthwind End With

In the code for the Open method, Customers is the name of the table and cnNorthwind is the name of the Connection object variable

Note

Closing the Recordset and Connection Objects

After you open a recordset and finish using it, you should close the recordset and release resources held by the object variables If you do not close the recordset, your application will waste memory and your recordset may keep a lock on a table, preventing other updates to the data To close a recordset and

remove the variable from memory, use the Close method of the Recordset object, and then set the object variable equal to Nothing

You should also use the Close method to close the Connection object when

you are done After closing the connection, you should also remove the object

variable from memory by setting it equal to Nothing

The following code closes and removes a Recordset object and a Connection

object from memory:

'Close objects and clean up rsCustomers.Close

cnNorthwind.Close Set rsCustomers = Nothing Set cnNorthwind = Nothing

Referencing Fields and Data

Referencing Fields in a Recordset

Populating Controls in an Outlook 2000 Form

rsCustomers.Fields("ContactName")

rsCustomers.Fields("ContactName")

' Populate.oftSet FormPages = _Item.Application.ActiveInspector.ModifiedFormPagesSet MembershipPage = FormPages("Get Data")

Set txtCompany = _MembershipPage.Controls("txtCompanyName")Set txtContact = _

MembershipPage.Controls("txtContactName")txtCompany.Text = rsCustomers.Fields("CompanyName")txtContact.Text = rsCustomers.Fields("ContactName")

' Populate.oftSet FormPages = _Item.Application.ActiveInspector.ModifiedFormPagesSet MembershipPage = FormPages("Get Data")

Set txtCompany = _MembershipPage.Controls("txtCompanyName")Set txtContact = _

MembershipPage.Controls("txtContactName")txtCompany.Text = rsCustomers.Fields("CompanyName")txtContact.Text = rsCustomers.Fields("ContactName")

When working with records in a recordset, you can programmatically refer to the fields of each record

Referencing Fields in a Recordset

The Fields collection of a Recordset object represents the Field objects in a

row of data or in a record To use a field in a record, refer to the field by name

The following code accesses the ContactName field of the rsCustomers

recordset:

rsCustomers.Fields("ContactName")

Populating Controls in an Outlook 2000 Form

After you have created a recordset, you can manually reference the fields of the recordset to present their values to the user For example, if the Outlook 2000 form that you are using has two text boxes—one text box to display the customer’s company name and a second text box to display the customer’s name—you can populate the text boxes manually This process must be repeated every time that the user navigates to a new record

The following code populates the text boxes on a form

' Populate.oft Set FormPages = _ Item.Application.ActiveInspector.ModifiedFormPages Set MembershipPage = FormPages("Get Data")

Set txtCompany = MembershipPage.Controls("txtCompanyName") Set txtContact = MembershipPage.Controls("txtContactName") txtCompany.Text = rsCustomers.Fields("CompanyName")

txtContact.Text = rsCustomers.Fields("ContactName")

Slide Objective

To show the different ways

that you can reference data

in a field

Lead-in

There are two ways to

access data in a field for the

current record in a

recordset

Navigating Records

Move Methods

MovePrevious

Using Move Methods to Create Navigation Buttons

BOF and EOF Properties

Sub cmdPrevious_Click()

' MoveMethods.oft rsCustomers.MovePrevious 'Check to see if tried to move prior to the _ first record

If rsCustomers.BOF Then

rsCustomers.MoveFirst End If

End Sub

Sub cmdPrevious_Click()

' MoveMethods.oft rsCustomers.MovePrevious 'Check to see if tried to move prior to the _ first record

If rsCustomers.BOF Then

rsCustomers.MoveFirst End If

End Sub

You can only access one record within a recordset at a given time The record currently being accessed is called the current record When you open a new recordset, the first record listed in the recordset becomes the current record by

default Navigation through a Recordset object is based on a record pointer A

record pointer indicates which record in the recordset is the current record Because only one record can be current, you navigate record-by-record by using

a variety of methods and properties to locate a specific record within the recordset Imagine that an invisible pointer highlights the current record as you move through the recordset

Move Methods

Five move methods enable you to navigate through the records in a Recordset object: Move, MoveFirst, MoveLast, MoveNext, and MovePrevious The

move methods allow a user to move to the first, last, next, or previous record in

a Recordset object and make that record the current record The following table

lists and describes when to use each of these move methods

Method Use to Move Move the position of the current record by the number of rows you

specify

MoveFirst Make the first record the current record

MoveLast Make the last record the current record

Slide Objective

To list the properties and

methods of the Recordset

object that support

navigation

Lead-in

Each Recordset object has

a current record You can

access different records in

the recordset by changing

the position of the current

record

(continued)

Method Use to MoveNext Make the next record the current record

If the last record is the current record and you call the MoveNext

method, the current record is set to the position after the last record inthe recordset, and end-of-file (EOF) is set to True An attempt to move forward beyond this point generates an error

MovePrevious Make the previous record the current record

If the first record is the current record and you call the

MovePrevious method, the current record is set to the position

before the first record in the recordset, and beginning-of-file (BOF) is set to True An attempt to move backward beyond this point

generates an error

To use move methods that move backward in the Recordset object, such

as the MovePrevious, MoveFirst, or Move method (when specifying the

NumRecords parameter as a negative number), the Recordset object must be

opened by using a value of the CursorType property that supports moving backward If you do not specify the CursorType property when opening a

Recordset object, the default value (adForwardOnly) will be used, which only

supports moving forward

Using Move Methods to Create Navigation Buttons

You can use the move methods to create and control navigation buttons in your application By using the navigation buttons, a user can navigate to specific records The following example responds to the Click event of the MoveFirst

button to navigate to the first record in the rsCustomers recordset

Sub cmdMoveFirst_Click() ' MoveMethods.oft rsCustomers.MoveFirst End Sub

The following example uses the Click event to create a MoveLast button that

navigates to the last record in the rsCustomers recordset

Sub cmdMoveLast_Click() ' MoveMethods.oft rsCustomers.MoveLast End Sub

Note

BOF and EOF Properties

You use the BOF and EOF properties to determine whether a Recordset object

contains records or to determine when you have moved beyond the records contained in a recordset while moving from record to record

When you open a Recordset object, the current record is positioned at the first record (if one exists) and the BOF and EOF properties are set to False The

BOF property returns True if the current record position is before the first

record The EOF property returns True if the current record position is after the last record If the recordset contains no records, the BOF and EOF property settings are both True The following example uses the BOF property in the

Click event to create a MovePrevious button that navigates to the previous

record in the rsCustomers recordset

Sub cmdPrevious_Click() ' MoveMethods.oft rsCustomers.MovePrevious 'Check to see if tried to move prior to the first record

If rsCustomers.BOF Then rsCustomers.MoveFirst End If

If rsCustomers.EOF Then rsCustomers.MoveLast End If

End Sub

In this example, if the user tries to move beyond the last record, the user is set back to the last record and the error is avoided

You can reduce the number of records that are returned to the Recordset object

by creating expressions that filter records from the selected tables or views The

Filter property on a Recordset object indicates a filter for data in a recordset Using the Filter Property

By using the Filter property of a Recordset object, you can limit the records

that are presented The original records are still available in memory, but only those records that meet the filter’s requirements will be displayed as part of the recordset

The following example shows only those customers that are located in the United Kingdom

rsCustomers.Filter = "Country = 'UK'"

Disabling a Filter

To return a recordset to its original contents, set the Filter property to the

adFilterNone constant The following example disables a filter, making all

original records available

rsCustomers.Filter = adFilterNone Setting the Filter property to "" (zero-length string) has the same effect as setting the property to adFilterNone

Slide Objective

To show how to filter

records

Lead-in

Filters enable you to

temporarily limit the records

available in a recordset,

without requiring your

application to run a new

query against the data

source