C#

Search and Navigation Improvements on MSDN

Mike McIntyre [MVP Visual Basic] — Sat, 26 May 2007 08:03:00 GMT

MSDN has had a face lift.

Visual Basic Development Center

For an explanation of the search and navigation imporovements visit:

Search and Navigation Improvements on MSDN

ADO.NET 2.0 The Series for Visual Basic 2005 and C# 2.0 - Part One

Mike McIntyre [MVP Visual Basic] — Wed, 07 Feb 2007 13:53:00 GMT

Source Code: ADO.NET 2.0 The Series - Part One

ADO.NET 2.0 The Series - Part One

This is part one of a multi-part article about ADO.NET 2.0. Part one introduces the ADO.NET 2.0 Object Model and provides source code which implements the ADO.NET Connection, Command, and Reader objects using the System.Data.SqlClient data provider.

The source code .zip file included with part one contains:

Visual Basic 2005 Windows Forms Application

C# 2005 Windows Forms Application

Application Screen Shot

The application opens a connection to a Sql Server database (Northwind database), runs a select command on the Northwind database's Categories table, reads the results returned, and displays the results in a RichTextbox control.

ADO.NET Object Model

The ADO.NET object model below presents the high level components of ADO.NET. Spend some time studying the model but don't worry if it is not completely clear at this point. It will be covered in depth in other parts of this article.

Data Provider Components

.NET Data Provider Namespaces

System.Data.SqlClient - Sql Server Data Provider

System.Data.OleDB - OLE DB Data Provider

System.Data.Odbc - ODBC Data Provider

System.Data.OracleClient - Oracle Data Provider

A data provider includes Connection, Command, Reader, and Adapter objects.

Data provider components are specific to a data source.

.NET data providers contain the same objects, but their names and some of their properties and methods differ. Examples:

SqlClient Data Provider - SqlConnection, SqlCommand, SqlDataReader, SqlDataAdapter

OleDB Data Provider - OleDbConnection, OleDbCommand, OleDbDataReader, OleDbDataAdapter

Odbc Data Provider - OdbcDbConnection, OdbcDbCommand, OdbcDbDataReader, OdbcDbDataAdapter

Data Provider Component Objects

Connection Object

Physical connection to data source

Determines the data provider used

Determines the data source and database

Adapter Object DataAdapter
Provides the bridge between a Connection object and a DataSet object

Contains four Command objects: Select, Insert, Update, and Delete

TableAdapter (new in ADO.NET 2.0)
Contains both a DataAdapter object and a Connection object.
Contains four Command objects: Select, Insert, Update, and Delete plus additional commands as defined by the programmer.

Command Object

SQL statement or stored procedure to be executed at the data source.

Use standalone or with the DataAdapter or TableAdapter.

Reader Object

Provides a fast, forward-only, read-only stream of data from a data source.
Used with a Command object

DataSet Object

Memory-resident

Always disconnected from the data source

Models tables and the relationships between them

Can contain tables from multiple data sources

Data Consumers

Data consumers are show with the ADO.NET objects in the ADO.NET Object Model to represent the applications, services, and other consumers that may call on the ADO.NET objects. In this article Windows Forms applications and ASP.NET applications will play the role of data consumers.

Implementing Connection, SqlCommand, and Reader Objects

The applications included in the .zip source code file demonstrate how to connect to a Sql Server, execute a Sql SELECT command, and read the results. Excerpts from the source code files are included below.

Visual Basic 2005 Code Excerpt

 
       ' Declare variable named theConnectionString of type String;
       '  Assign a connection string to theConnectionString variable.
       ' NOTE: To run this yourself replace the connection string with a connection string to a
       '  SQL Server with the Northwind database installed that you have permission to access.
       Dim theConnectionString As String = "Data Source=az-4ffd1ee68bce;Initial Catalog=Northwind;Integrated Security=True"
 
       ' Declare a variable named theQueryString of type String;
       '  Assign a string containing a SQL SELECT command to theQueryString
       Dim theQueryString As String = "SELECT CategoryID, CategoryName FROM dbo.Categories;"
 
       ' The Visual Basic 2005 'Using' keyword simplifies the use of Dispose methods by
       '  automatically calling dispose for an object.
       ' The keyword is used here to create a SqlConnection object.
       Using theSqlConnection As New SqlConnection(theConnectionString)
 
           ' Declare variable named theSqlCommand of type SqlCommand
           '  calling theSqlConnection object's CreateCommand method
           '  and assigning the resulting SqlCommand object to theSqlCommand variable.
           Dim theSqlCommand As SqlCommand = theSqlConnection.CreateCommand()
           ' Assign theQueryString to theSqlCommand's CommandText property.
           theSqlCommand.CommandText = theQueryString
           Try
               ' Open theSqlConnection.
               theSqlConnection.Open()
 
               ' Declare variable named theSqlDataReader of type SqlDataReader
               '  calling theSqlCommand object's ExecuteReader method
               '  and assigning the resulting cursor to theSqlDataReader varaiable.
               Dim theSqlDataReader As SqlDataReader = theSqlCommand.ExecuteReader()
 
               ' Call theSqlDataReader object's Read method until then end
               '  of the cursor is reached.
               Do While theSqlDataReader.Read()
                   ' Append a formatted string containing column 0 and column 1 of the row read
                   '  to the ResultsRichTextBox.
                   Me.ResultsRichTextBox.AppendText(String.Format("{0}" & vbTab & "{1}", _
                   theSqlDataReader(0), theSqlDataReader(1)) & vbCrLf)
               Loop
               ' Close theSqlDataReader
               theSqlDataReader.Close()
           Catch ex As Exception
               Console.WriteLine(ex.Message)
           End Try
       End Using

C# 2005 Code Excerpt

 // Declare variable named theConnectionString of type String;
 //  Assign a connection string to theConnectionString variable.
 // NOTE: To run this yourself replace the connection string with a connection string to a
 //  SQL Server with the Northwind database installed that you have permission to access.
 string theConnectionString = "Data Source=az-4ffd1ee68bce;Initial Catalog=Northwind;Integrated Security=True";
 
 // Declare a variable named theQueryString of type String;
 //  Assign a string containing a SQL SELECT command to theQueryString variable.
 string theQueryString = "SELECT CategoryID, CategoryName FROM dbo.Categories;";
 
 // The C# 'Using' keyword simplifies the use of Dispose methods by
 //  automatically calling dispose for an object.
 // The keyword is used here to create a SqlConnection object.
 using (SqlConnection theSqlConnection = new SqlConnection(theConnectionString))
 {
    // Declare variable named theSqlCommand of type SqlCommand
    //  calling theSqlConnection object's CreateCommand method
    //  and assigning the resulting SqlCommand object to theSqlCommand variable.
    SqlCommand theSqlCommand = theSqlConnection.CreateCommand();
    // Assign theQueryString to theSqlCommand's CommandText property.
    theSqlCommand.CommandText = theQueryString;
    try
    {
        // Open theSqlConnection.
        theSqlConnection.Open();
 
        // Declare variable named theSqlDataReader of type SqlDataReader
        //  calling theSqlCommand object's ExecuteReader method
        //  and assigning the resulting cursor to theSqlDataReader varaiable.
        SqlDataReader theSqlDataReader = theSqlCommand.ExecuteReader();
 
        // Call theSqlDataReader object's Read method until then end
        //  of the cursor is reached.
        while (theSqlDataReader.Read())
        {
            // Append a formatted string containing column 0 and column 1 of the row read
            //  to the ResultsRichTextBox.
            this.resultsRichTextBox.AppendText(string.Format("{0}" + "\t" + "{1}", theSqlDataReader[0], theSqlDataReader[1]) + "\r");
        }
 
        // Close theSqlDataReader
        theSqlDataReader.Close();
    }
    catch (Exception ex)
    {
        Console.WriteLine(ex.Message);
    }
 }

For more information:

SqlConnection Class

SqlCommand Class

SqlDataReader Class

mike mcintyre http://www.getdotnetcode.com

Microsoft AJAX Series Part 6 - PageRequestManager

Mike McIntyre [MVP Visual Basic] — Wed, 13 Dec 2006 15:13:00 GMT

Source Code: Microsoft AJAX Series Part 6 - PageRequestManager

Microsoft AJAX Series Part 6 - PageRequestManager

This is the sixth in a series of blog posts about Microsoft ASP.NET AJAX, a new web development technology from Microsoft.

Click these links to view previous posts in this series: Post 1, Post 2, Post 3, Post 4 and Post 5

This article introduces the Microsoft Ajax PageRequestManager object and demonstrates how to handle its pageLoaded event to it trigger an animation when a page is updated after an asynchronous post back.

PageRequestManager Overview

The PageRequestManager class in the Microsoft AJAX Library manages partial-page rendering on the client.

When you have a ScriptManager and one or more UpdatePanel controls on the page, the page is automatically enabled for partial-page rendering.

The PageRequestManager exposes properties, methods, and events that allow you to customize the partial-page rendering experience with client script.

Scenarios

Provide custom error message handling for partial-page rendering.
Control multiple asynchronous postbacks.
Display status messages during asynchronous postbacks.
Access the underlying request and response objects used in an asynchronous postback.

Partial-Page Rendering Event Handling

During page processing (both postbacks and asynchronous postbacks), you can handle DOM events to run custom script.

However, these DOM events do not enable you to access information or control the behavior during asynchronous postbacks and during partial-page updates that occur between the load and unload of the page in the browser.

The PageRequestManager class exposes the following events that enable you to customize partial-page rendering:

initializeRequest
beginRequest
pageLoading
pageLoaded
endRequest

About the Source Code

The source code implements an ASP.NET 2.0 web application that shows how you can use the pageLoaded event of the PageRequestManager class to animate an UpdatePanel control when the page is updated after an asynchronous postback.

In this web page shown above, users can select a date and enter an email address into a simple form to make a ticket request. When certain elements postback from the page ( (1) above), the panel is animated briefly to notify the user that the date value was entered into the text box. The page contains a popup that displays a Calendar control. The calendar is displayed or hidden using the control's Visible property. Hiding, showing, or selecting dates in the calendar does not cause the entire page to be refreshed, because the Calendar control is inside an UpdatePanel control.

The source code included with this post (see download link above) includes additional comments about the example.

The source code was created with ASP.NET AJAX 1.0 Beta 2. For more information and FREE Microsoft ASP.NET Ajax installers visit -> The Official Microsoft ASP.NET AJAX Website

mike mcintyre http://www.getdotnetcode.com

Microsoft ASP.NET AJAX the Series Part 5 - Call Web Service With JavaScript

Mike McIntyre [MVP Visual Basic] — Tue, 05 Dec 2006 20:15:00 GMT

Source Code: Microsoft ASP.NET AJAX the Series Part 5 - Call Web Service With JavaScript

This is the fifth in a series of blog posts about Microsoft ASP.NET AJAX, a new web development technology from Microsoft.

Click these links to view previous posts in this series: Post 1, Post 2, Post 3, and Post 4

This post introduces the Microsoft Ajax asynchronous communication layer and demonstrates how to use it to call a web service, from a client, using JavaScript.

Asynchronous Communication Layer

The asynchronous communication layer is the foundation for very responsive client Web application presentation.

The layer enables more separation between the business and data tiers on the server and the presentation tier on the client. It makes it easier to do more processing client side. In this context, the browser has full control of the presentation tier and provides a rich and responsive user interface, while the server performs the business and data tier tasks.

The layer exposes functionality for browser asynchronous behavior provided by the XMLHTTP object as a set of APIs that JavaScript functions can use from any browser to call Web service methods on the server. The XMLHTTP object enables the browser to send asynchronous HTTP requests and return data that can be processed in client script.

What can you do through the asynchronous communication layer?

Asynchronous postbacks and partial-page rendering
Invoke methods in Web services implemented as .asmx files
Invoke specifically enabled ASP.NET page methods
Supports a variety of serialization formats for passing data between the browser and the server
Optimize Web service interactions by pre-loading and caching JavaScript proxies used to communicate with the Web services on a server

About the Source Code

The source code includes a Web service whose proxy class is used by the browser and an ASP.NET Web page containing client script that calls a page method and a web service. Here is a screen shot of the web page:

The source code included with this post (see download link above) demonstrates how to call a web service with JavaScript. Additional comments about the process are included in the example page and source code.

The source code was created with ASP.NET AJAX 1.0 Beta 2 which is available at -> The Official Microsoft ASP.NET AJAX Website

The next post in this series will explore the Microsoft Ajax Page Manager object.

For more information and FREE Microsoft ASP.NET Ajax installers visit -> The Official Microsoft ASP.NET AJAX Website

mike mcintyre http://www.getdotnetcode.com

Microsoft ASP.Net AJAX the Series Post 3 - Nested UpdatePanels

Mike McIntyre [MVP Visual Basic] — Mon, 20 Nov 2006 08:56:00 GMT

VB Source Code: AJAXBeta2UpdatePanelNested_VB.zip

C# Source Code: AJAXBeta2UpdatePanelNested_CS.zip

This is the third in a series of blog posts about Microsoft ASP.Net AJAX, a new web development technology from Microsoft.

The first and second post in this series introduced Ajax technologies and Microsoft AJAX, and, in a 'Hello World' example, introduced the UpdatePanel server control.

Nest UpdatePanel Controls

UpdatePanel controls can be nested.

Nesting an UpdatePanel within another UpdatePanel gives a finer level of control over partial page rendering.

If a parent UpdatePanel is refreshed, all nested UpdatePanels are also refreshed as well.

If a nested UpdatePanel is refreshed its parent UpdatePanel is by default, not refreshed.

The source code included with this post (see download links above) demonstrates how to implement partial page rendering with the ASP.NET 2.0 ScriptManager and an UpdatePanel containing a nested UpdatePanel control. Additional comments about these controls is included in the example page and source code.

The source code was created with ASP.NET AJAX 1.0 Beta 2 which is available at -> The Official Microsoft ASP.Net AJAX Website

The next post in this series will delve more deeply into partial page rendering with the UpdatePanel control.

For more information and FREE Microsoft ASP.NET Ajax installers visit -> The Official Microsoft ASP.Net AJAX Website

mike mcintyre http://www.getdotnetcode.com

Microsoft ASP.Net AJAX the Series Post 2 - What is Microsoft's ASP.NET AJAX?

Mike McIntyre [MVP Visual Basic] — Fri, 10 Nov 2006 09:01:00 GMT

VB Source Code: Hello World ASP.NET AJAX Beta 2 - Visual Basic 2005

C# Source Code: Hello World ASP.NET AJAX Beta 2 - C# 2.0

This is the second in a series of blog posts about Microsoft ASP.Net AJAX, a new web development technology from Microsoft.

The previous post in this series provided a definition of Ajax: A term used to refer to a group of technologies used, in various combinations, to create web applications that are more interactive and responsive, and which provide a richer client-side experience, than what is found in classic web applications.

What is Microsoft's ASP.NET AJAX?

Web applications built with Ajax technologies can be referred to as Ajax-style applications.

ASP.NET AJAX is a development framework for developing Ajax-style applications. Its main purpose is to simplify the development of Ajax-style applications. Until now, creating Ajax-style applications has been fairly complicated and time consuming. ASP.NET AJAX simplifies the development of Ajax-style applications through features such as:

ASP.NET server controls that emit client-side JavaScript to reduce or eliminate the JavaScript you must write when you create an Ajax-style application;

An asynchronous communication layer that abstracts away the complexity of adding asynchronous postbacks and partial page rendering to an Ajax-style application;

Beneficial integration between the client-side Microsoft AJAX JavaScript libraries and the ASP.NET 2.0 server-based development framework for example, by providing client-side integration with server-side ASP.NET 2.0 authentication and profiles services and ASP.NET 2.0 web services created by developers.

Browser independence: what you create with ASP.NET AJAX will work across all the major browsers without modification;

Client-side APIs and components to support rich UI features - such as drag-and-drop and auto-completion - to save you from having to write the extensive code normally required for such rich UI features in Ajax-style applications.

Add ASP.NET AJAX Functionality to a Web Page

To add AJAX functionality to an ASP.NET Web page: (1) add an ASP.NET AJAX ScriptManager server control to the page; (2) identify individual sections of your page that you want to update; and (3) wrap each of the identified sections with an ASP.NET AJAX UpdatePanel server control.

The ASP.NET 2.0 ScriptManager control coordinates and tracks ASP.NET AJAX activity for an ASP.NET web page. To enable ASP.NET AJAX activity on an ASP.NET page you must add a ScriptManager control to the page. Note: If you place a ScriptManager on a master page it coordinates and tracks ASP.NET AJAX activity for the children of that master page. You can not add a ScriptManager to a child of a master page that already contains a ScriptManager control.

The ASP.NET 2.0 UpdatePanel control enables sections of a page to be partially rendered without a postback. You identify sections of the page you wish to participate in partial rendering and 'wrap' each such section with an UpdatePanel control. Note: The ScriptManager control keeps track of all the update panels on the page. It coordinates the partial-page rendering behavior on the server and instructs the page what sections of the page to render as a result of the last asynchronous postback.

Hello ASP.NET AJAX

The source code included with this post (see download links above) is a very simple 'Hello World' program created with ASP.NET AJAX. It demonstrates how to implement partial page rendering with the ASP.NET 2.0 ScriptManager and UpdatePanel controls. Additional comments about these controls is included in the example page and source code.

The source code was created with ASP.NET AJAX 1.0 Beta 2 which is available at -> The Official Microsoft ASP.Net AJAX Website

The next post in this series will delve more deeply into partial page rendering.

For more information and FREE Microsoft ASP.NET Ajax installers visit -> The Official Microsoft ASP.Net AJAX Website

mike mcintyre http://www.getdotnetcode.com

Microsoft ASP.Net AJAX the Series - What is Ajax?

Mike McIntyre [MVP Visual Basic] — Tue, 07 Nov 2006 06:40:00 GMT

This is the first in a series of blog posts about ASP.Net AJAX, a new web development technology from Microsoft.

A series about ASP.Net AJAX must start by first answering the question: "What is Ajax?"

Ajax is a term used to refer to a group of technologies used, in various combinations, to create web applications that are more interactive and responsive, and which provide a richer client-side experience, than what is found in classic web applications.

Ajax Technologies

Extensible HyperText Markup Language (XHTML)
Document Object Model (DOM)
Cascading Style Sheets (CSS)
Client Side Scripting (most commonly with JavaScript)
XMLHttpRequest (XHR)
Data Transport Languages (most commonly used are XML and JSON)

For an explanation of an individual Ajax technology click the name of the technology above.

For Wikipedia's definition of Ajax click here -> Ajax (programming) - Wikipedia, the free encyclopedia

To get a feel for the interactivity, performance, and richer client-side experience of Ajax web applications, visit the sites below.

Page Flakes
Mash Up (combines content from more than one source into an integrated experience)
Personalizable Web Desktop

Windows Live
Mash Up
Personalizable Web Desktop

Windows Local
Mash Up
Personalizable Geo Information

All forthcoming posts in this series will include downloadable ASP.Net AJAX examples in Visual Studio 2005 solutions for both Visual Basic 2005 and C#.

The next post in this series will answer the question: "What is Microsoft ASP.Net AJAX?" and will introduce the ASP.NET AJAX v1.0 Beta UpdatePanel server control.

For more information and FREE Microsoft ASP.NET Ajax installers visit -> The Official Microsoft ASP.Net AJAX Website

mike mcintyre http://www.getdotnetcode.com

New Graphics for Application Development in Visual Studio 2005

Mike McIntyre [MVP Visual Basic] — Sun, 23 Oct 2005 18:12:00 GMT

When you install Visual Studio 2005 be sure to unzip the new graphics collection at:

C:\Programs\Microsoft Visual Studio 8\Common7\VS2005ImageLibrary.zip

Enjoy!

Free Sql Server 2005 and Visual Studio 2005 eLearning Courses From Microsoft

Mike McIntyre [MVP Visual Basic] — Sat, 11 Jun 2005 17:49:00 GMT

And the free stuff keeps coming....

There are 17 FREE eLearning courses now available from Microsoft Learning dedicated to preparing you for Sql Server 2005 and Visual Studio 2005 These eLearning courses and corresponding course descriptions can be found at:

https://www.microsoftelearning.com/visualstudio2005/
https://www.microsoftelearning.com/sqlserver2005/

Connection Object Physical connection to data source Determines the data provider used Determines the data source and database
Adapter Object	DataAdapter Provides the bridge between a Connection object and a DataSet object Contains four Command objects: Select, Insert, Update, and Delete
	TableAdapter (new in ADO.NET 2.0) Contains both a DataAdapter object and a Connection object. Contains four Command objects: Select, Insert, Update, and Delete plus additional commands as defined by the programmer.
Command Object SQL statement or stored procedure to be executed at the data source. Use standalone or with the DataAdapter or TableAdapter.
Reader Object Provides a fast, forward-only, read-only stream of data from a data source. Used with a Command object