Error: The 'Microsoft.Jet.OLEDB.4.0' provider is not registered on the local machine.

Error: The 'Microsoft.Jet.OLEDB.4.0' provider is not registered on the local machine. I got this error when I tried to run my .NET application into VS 2010 with 64 bit OS/machine, to resolve this issue we have to forcefully set application setting to run this application for 32 bit, to do that please follow the steps below 1) Right click on the project and click on the properties 2) Go to the Build tab 3) Set Platform target from "Any CPU" to x86 4) Now run your application again, you will not get this error again.

Error: ASP.NET Ajax client-side framework failed to load. OR 'Sys' is undefined.

Error: ASP.NET Ajax client-side framework failed to load. OR 'Sys' is undefined. in VS 2008

Cause:

I got this error very first time when I tried to use AJAX ScriptManager object using VS2008.

I was tring to registred script using ScriptManager like below

protected void Button1_Click(object sender, EventArgs e)

{

ScriptManager.RegisterStartupScript(

this,this.GetType(),"script","alert('Hi');",true);

}

Solution:

I found there are two way to solve this error

1) You need to add httpHandlers into the web.config below "compilation" tag

Code:

<!--Ajax -->

<httpHandlers>

<remove verb="*" path="*.asmx"/>

<add verb="*" path="*.asmx" validate="false" type="System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions,

Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/>

<add verb="GET" path="ScriptResource.axd" type="System.Web.Handlers.ScriptResourceHandler" validate="false"/>

</httpHandlers>

<compilation debug="true">

2) You can solve this error by using RegisterAsyncPostBackControl method

Using beolw code button control will not have any page refresh like a client control.

Code:

protected void Page_Load(object sender, EventArgs e)

{

// register the Button1 control as one that can cause partial postbacks.

ScriptManager1.RegisterAsyncPostBackControl(Button1);

}

Note: I may not get this error in latest version/patch of VS2008.

Combo box Auto Complete Property in C# and VB using .NET

Combo box Auto Complete Property in C# and VB using .NET

When you have a requirement for combo box control like: when user types some text/number then combo box should display/select value as per user typing the characters from keyboard.

Ex: If Combo Box having following items (Source code load the combo box value)

ComboBox1.Items.Add("ABC123")

ComboBox1.Items.Add("AABC123")

ComboBox1.Items.Add("AAABC123")

ComboBox1.Items.Add("AAAABC123")

ComboBox1.Items.Add("CCCEF123")

ComboBox1.Items.Add("1123ABC")

ComboBox1.Items.Add("2234BCD")

ComboBox1.AutoCompleteSource = AutoCompleteSource.ListItems

ComboBox1.DropDownStyle = ComboBoxStyle.DropDownList

and requirement is when user type in the combo box the relative text should display

Ex: When user type "A" then combo box should select "ABC123" value from the list

When user type "AA" then combo box should select "AABCD123" value from the list

When user type "AAA" then combo box should select "AAABC123" value from the list

etc.

To achieve above requirements, very simple in .NET to use "ComboBox1.AutoCompleteMode" property, it has 4 mode and default is "None"

1) AutoCompleteMode.Append

This Mode will append the value as user type the character one by one and select the nearest value in the combo box

2) AutoCompleteMode.Suggest

This Mode will select the nearest value in the combo box when user type ONLY first characher in the combo box and will open (Drop) the combo box to suggest the other nearest possible value present in the combo box

Ex:

3) AutoCompleteMode.SuggestAppend
This Mode will append the value as user type the characters one by one and select the nearest value in the combo box and also will open (Drop) the combo box to suggest the other nearest possible value present in the combo box
4) AutoCompleteMode.None (Default)
This Mode will select the nearest value in the combo box when user type ONLY first characher in the combo box

How to create ASP.NET Web Parts for Windows SharePoint Services 3.0

Good video to learn how to create web part using ASP.net 3.0.

Get idea about web part and how to use in Share Point Service 3.0.

Full screen

http://mschnlnine.vo.llnwd.net/d1/ch9/2/2/4/7/8/1/192071_AspWebPartsForWss3.wmv

What is “unsafe” Keyword in C#.NET

What is "unsafe" Keyword in C#.NET

In C# the value can be directly referenced to a variable, so there is no need of pointer. Use of pointer sometime crashes the application. But C# supports pointer and we can use pointer in C#.

The use of pointer in C# is defined as an unsafe code. So if we want to use pointer in C# the pointer must be present in the body of unsafe declaration. But pointer does not come under garbage collection.

Example:-

unsafe

{

int firstVariable;

int* secondPointerVariable;

firstVariable = 25;

secondPointerVariable = &firstVariable;

Console.WriteLine("secondPointerVariable = {0}", secondPointerVariable);

//returns secondPointerVariable = 25

}

Note: you may get compilation error ("Unsafe code may only appear if compiling with /unsafe") while compiling the above code.

If you' are compiling from the command line then include the /unsafe switch as the error suggests.
If you're compiling from Visual Studio, then look in your project's properties and, under the build tab, check the 'Allow unsafe code' box. It should work fine.

How to make an application offline in ASP.NET

How to make an application offline in ASP.NET

Microsoft's Internet Information Services (IIS) web server software is used to make an application offline. The IIS is instructed to route all incoming requests for the web site to another URL automatically.

Steps for application configuration:

• From IIS manager -> right-click on the application -> choose Properties.
• Choose Virtual Directory tab and indicate that the content for this application should come from "A redirection to a URL."
• Then enter the same URL to redirect in "Redirect to".
• Check the box "The exact URL entered above.

Read more way to do the same.

http://aspalliance.com/1666_How_to_Make_an_Application_Offline_in_ASPNET_20.all

Web Service Vs WCF (Window Communication Foundation)

Web Service Vs WCF (Window Communication Foundation)

WCF is a set of .NET Framework-based technologies for building and running services. WCF is the next step in the evolutionary path that started with COM, COM+, and MSMQ, and continues through .NET Remoting, ASMX, System.Messaging, and .NET Enterprise Services. WCF combines these technologies and offers a unified programming model for developing services using any CLR-compliant language.

Feature	ASP.NET Web Service	WCF
Performance	Slower compared to WCF	The main benifit of the design of the DataContractSerializer is better performance over XML serialization
File Extension	File extention is asmx	File extension is .svc
Data Transformation	To and from Data Transition is done through XML Serializer	DataContractSerializer is used for data transition
Webmethods vs DataContract Attributes	ASP.NET WebService uses Webmethods to to translate .NET FW types in to XML.	The WCF uses the DataContractAttribute and DataMemeberAttribute to translate .NET FW types in to XML.
Limitations	Only Public fields or Properties of .NET types can be translated into XML.Only the classes which implement IEnumerable interface, ICollection interface can be serializable	Public/Private fields or properties of .NET types can be translated
IDictionary Interface class	Classes that implement the IDictionary interface, such as Hash table can not be serialized.	The DataContractSerializer can translate the Hash Table into XML. Hence using WCF we can even translate HashTable into XML
Know which fields /properties	XMLSerialization does not indicate the which fields or properties of the type are serialized into XML	DataCotratSerializer Explicitly shows the which fields or properties are serialized into XML
Exception handling	In ASP.NET Web services, Unhandled exceptions are returned to the client as SOAP faults.	In WCF Services, unhandled exceptions are not returned to clients as SOAP faults. A configuration setting is provided to have the unhandled exceptions returned to clients for the purpose of debugging.
Example	[WebService] public class Service : System.Web.Services.WebService { [WebMethod] public string Demo(string strDemog) { return strDemo; } }	[ServiceContract] public interface ITest { [OperationContract] string Demo (string strDemo); } public class Service : ITest { public string Demo(string strDemo) { return strDemo; } }

Learn more about WCF

http://www.xvpj.net/2008/03/08/wcf-step-by-step-tutorial/

http://www.15seconds.com/Issue/061130.htm

Multiple rows getting selected on mouse move when I am closing ContextMenuStrip by clicking datagridview row

Multiple rows getting selected on mouse move when I am closing ContextMenuStrip by clicking datagridview row

Note: Before looking solution for this issues you have to understand how to do drag and drop from one datagridview to another, See here http://riteshk.blogspot.com/2009/06/how-to-change-mouse-icon-when-drag_23.html

This issue is related to DataGridView DragDropEffects.Move,When you open sub menu from datagridview mouse down event and you have code to activate drag drop event too then on click of datagridview row, control in activating dagDropEffects.Move and when you move the mouse after closing the sub menu, mouse cousor having same effect (Move) and it will select multiple rows on the mouse move event.

Solution

To overcome this problem we have to ignore activating "DragDropEffects.Move" by putting some condition when sub menu get pops up

In the below code I have placed one boolean flag (isSubMenuClicked) and setting true when sub menu display otherwise its false

and check if "columnIndex > -1 and isSubMenuClicked = False" then only control should go and activate the datagridview dragdrop

DataGridView MouseDoubleClick not getting fire

Another problem here on the mouse double click "DataGridView1.DoDragDrop" should not get activate, other wise datagridview mouse double click will not get fire

Solution

To overcome this problem you have to check whether mouse button clicked once or twiced for that I have placed one condition in below code

its "If e.Clicks = 1 Then"

Source Code

Private Sub DataGridView1_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles DataGridView1.MouseDown

Dim gridColumnIndex As Integer

'Get the Index of Row which is being Dragged

'We would use this Index on Drop to identify which Row was dragged and get the values from that row

If e.Button = Windows.Forms.MouseButtons.Left Then

gridColumnIndex = DataGridView1.HitTest(e.X, e.Y).RowIndex

'For Mouse Single Click Only

If e.Clicks = 1 Then

'If Grid have any row and sub menu not display

If gridColumnIndex > -1 And isSubMenuClicked = False Then

DataGridView1.DoDragDrop(gridColumnIndex, DragDropEffects.Move)

Else

DataGridView1.ClearSelection()

End If

End If

End If

Dim hitRowIndex As Integer

hitRowIndex = DataGridView1.HitTest(e.X, e.Y).RowIndex

'Open Sun Menu only on Mouse Right click and

'Avoid sub menu to display on datagridview header click

If (e.Button = Windows.Forms.MouseButtons.Right And hitRowIndex > -1) Then

ContextMenuStrip1.Show(DataGridView1, New Point(e.X, e.Y))

isSubMenuClicked = True

Else

isSubMenuClicked = False

End If

End Sub

How to check which version of the dotnet framework is installed

1) Go To Start and click on Run
2) Type --> "%windir%\Microsoft.NET\Framework\"
You will see all the version installed folder name (Ex: v1.0.3705, v1.1.4322, v2.0.50727, v3.0, v3.5)

How to Display/Hide Crystal Report Viewer Tab and Status Bar at run time using VB.NET

How to Display/Hide Crystal Report Viewer Tab and Status Bar at run time using VB.NET I am working with Visual Studio 2005 and faced some issues while working with crystal report, my requirement is to display and hide tab and status bar control from crystal report viewer, event tab control should display customized name in the tab text. I found the way to do this, below the code in vb.net Display/Hide crystal report viewer tab control and rename the tab control ''' <summary> ''' This method will make tab controls visibile True/False ''' </summary> ''' <remarks>Ritesh</remarks> Private Sub CrystalReportViewerTab(ByVal rptViewer As CrystalDecisions.Windows.Forms.CrystalReportViewer, ByVal isVisible As Boolean) Dim reportTabs As TabControl = rptViewer.Controls(0).Controls(0) 'if tab visible If isVisible Then With reportTabs .ItemSize = New Size(70, 18) .SizeMode = TabSizeMode.FillToRight .Appearance = TabAppearance.Normal 'Here you can give customize name to tab .TabPages(0).Text = "My Tab Text" End With Else 'if tab hide With reportTabs .ItemSize = New Size(0, 1) .SizeMode = TabSizeMode.Fixed .Appearance = TabAppearance.Buttons End With End If End Sub Display/Hide crystal report viewer status bar ''' This method will make status bar visibile True/False Public Sub CrystalReportViewerStatusBar(ByVal rptViewer As CrystalDecisions.Windows.Forms.CrystalReportViewer, ByVal isVisible As Boolean) Dim ctl As Control For Each ctl In rptViewer.Controls If ctl.GetType().Name.ToString() = "StatusBar" Then ctl.Visible = isVisible End If Next End Sub