Ali Raza Zaidi

Musing's of ERP Consultant

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.net framework 2

How to get month date view between two dates in c#

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Scenario I got while developing some application. I required month and year view in drop down list between contract starting and ending date. Like “March 2009” “April 2009” until march 2011 so on.

I handled it as follow

DateTime _LoopDate = “1/1/2009”;
string month = string.Empty;
DateTime _EndDate = “1/1/2011”;

while (_LoopDate <= _EndDate)
{
System.Globalization.DateTimeFormatInfo d = new System.Globalization.DateTimeFormatInfo();
month = d.MonthNames[_LoopDate.Month – 1];

drpDate.Items.Add(new ListItem(month + ” ” + _LoopDate.Year.ToString(), _LoopDate.Month.ToString() + ” ” + _LoopDate.Year.ToString()));
//drpdate is dropdownlist
_LoopDate= _LoopDate.AddMonths(1);
}

how to send mail smtp with authentication with web.mail class

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hi i used following code

MailMessage message = new MailMessage();

message.To = "myemailaccount@yahoo.com";

message.From = "myemailaccount@thecrystalrosary.com";
message.Subject = "Testing Internet SmtpMail";
message.BodyFormat = MailFormat.Html;

message.Body = "body";

message.Fields.Add("http://schemas.microsoft.com/cdo/configuration/smtpserver", "smtp.thecrystalrosary.com");
message.Fields.Add("http://schemas.microsoft.com/cdo/configuration/smtpserverport", 25);
message.Fields.Add("http://schemas.microsoft.com/cdo/configuration/sendusing", 2); //2 to send using SMTP over the network
message.Fields.Add("http://schemas.microsoft.com/cdo/configuration/smtpauthenticate", 1); //1 = basic authentication
message.Fields.Add("http://schemas.microsoft.com/cdo/configuration/sendusername", "username");
message.Fields.Add("http://schemas.microsoft.com/cdo/configuration/sendpassword", "password");

try
{
SmtpMail.Send(message);
}
catch (Exception e)
{
// trap here
}

how to get oracle sequence numbers in .net

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hi the main Query to get sequence number is follow


select JOB_ID_SEQ.NEXTVAL from dual;

i get the required Sequence number value form following method

public int GetOracleSequenceValue(string _SequenceValue)
{
OdbcCommand _command = new OdbcCommand();
int _ItemValue = -1;
OdbcConnection _con = new OdbcConnection(System.Web.Configuration.WebConfigurationManager.ConnectionStrings["RCConnectionString"].ToString());
try
{
_con.Open();
_command.Connection = _con;
string _QueryString = "select "+ _SequenceValue +" from dual ";
_command.CommandText = _QueryString;
_ItemValue = Convert.ToInt32(_command.ExecuteScalar().ToString());
_con.Close();
}
catch (Exception ex)
{
Util.LogErrorToFile(ex, "MYExecuteNonQuery", "error");
}
finally
{
_con.Close();
}
return _ItemValue;
}

Chears

How to resize image in .net

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use follwing Code change image path at load event method for downloading Code

Imports System
Imports System.Drawing
Imports System.Drawing.Imaging
Imports System.Drawing.Drawing2D
Public Class Form1

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim WorkingDirectory As String = "c:AliPicture"

'create a image object containing a verticel photograph
Dim imgPhotoVert As Image = Image.FromFile(WorkingDirectory + "pravs-j-the-first-step.jpg")
Dim imgPhoto As Image = Nothing
imgPhoto = FixedSize(imgPhotoVert, 100, 100)
imgPhoto.Save(WorkingDirectory + "imageresize_3.jpg", ImageFormat.Jpeg)
imgPhoto.Dispose()

End Sub

Private Shared Function FixedSize(ByVal imgPhoto As Image, ByVal Width As Integer, ByVal Height As Integer) As Image
Dim sourceWidth As Integer = imgPhoto.Width
Dim sourceHeight As Integer = imgPhoto.Height
Dim sourceX As Integer = 0
Dim sourceY As Integer = 0
Dim destX As Integer = 0
Dim destY As Integer = 0

Dim nPercent As Single = 0
Dim nPercentW As Single = 0
Dim nPercentH As Single = 0

nPercentW = (CSng(Width) / CSng(sourceWidth))
nPercentH = (CSng(Height) / CSng(sourceHeight))

'if we have to pad the height pad both the top and the bottom
'with the difference between the scaled height and the desired height
If nPercentH < nPercentW Then
nPercent = nPercentH
destX = CInt(((Width - (sourceWidth * nPercent)) / 2))
Else
nPercent = nPercentW
destY = CInt(((Height - (sourceHeight * nPercent)) / 2))
End If

Dim destWidth As Integer = CInt((sourceWidth * nPercent))
Dim destHeight As Integer = CInt((sourceHeight * nPercent))

Dim bmPhoto As New Bitmap(Width, Height, PixelFormat.Format24bppRgb)
bmPhoto.SetResolution(imgPhoto.HorizontalResolution, imgPhoto.VerticalResolution)

Dim grPhoto As Graphics = Graphics.FromImage(bmPhoto)
grPhoto.Clear(Color.Red)
grPhoto.InterpolationMode = InterpolationMode.HighQualityBicubic

grPhoto.DrawImage(imgPhoto, New Rectangle(destX, destY, destWidth, destHeight), New Rectangle(sourceX, sourceY, sourceWidth, sourceHeight), GraphicsUnit.Pixel)

grPhoto.Dispose()
Return bmPhoto
End Function

End Class

how to get server.mappath in c# class

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i face a problem that server.mappath did not available in c# class at my utillity framework at app code folder of one of my asp.net application.  While it is available at asp.net page code behind.  Because ASP.NET pages contain a default reference to the System.Web namespace (which contains the
HttpContext class), you can reference the members of HttpContext on an .aspx
page without the fully qualified class reference to HttpContext.

For using Server.MapPath at C# class i used it following

System.Web.HttpContext.Current.Server.MapPath(logpath);

Design Patterns Interview Questions

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What is a Design Pattern?

Design Pattern is a re-usable, high quality solution to a given requirement, task or recurring problem. Further, it does not comprise of a complete solution that may be instantly converted to a code component, rather it provides a framework for how to solve a problem.

In 1994, the release of the book Design Patterns, Elements of Reusable Object Oriented Software made design patterns popular.

Because design patterns consist of proven reusable architectural concepts, they are reliable and they speed up software development process.

Design Patterns are in a continious phase of evolution, which means that they keep on getting better & better as they are tested against time, reliability and subjected to continious improvements. Further, design patterns have evolved towards targeting specific domains. For example, windows-based banking applications are usually based on singleton patterns, e-commerce web applications are based on the MVC (Model-View-Controller) pattern.

Design Patterns are categorized into 3 types:
Creational Patterns
Structural Patterns
Behavioral Patterns

What are Creational Design Patterns?

The Creational Design Patterns focus on how objects are created and utilized in an application. They tackle the aspects of when and how objects are created, keeping in mind whats the best way these objects should be created.

Listed below are some of the commonly known Creational Design Patterns:
>>> Abstract Factory Pattern
>>> Factory Pattern
>>> Builder Pattern
>>> Lazy Pattern
>>> Prototype Pattern
>>> Singleton Pattern

Whats the difference between Abstract Factory Pattern and Factory Pattern?

In an abstract factory design, a framework is provided for creating sub-components that inherit from a common component. In .NET, this is achieved by creating classes that implement a common interface or a set of interfaces, where the interface comprises of the generic method declarations that are passed on to the sub-components. TNote that not just interfaces, but even abstract classes can provide the platform of creating an application based on the abstract factory pattern.
Example, say a class called CentralGovernmentRules is the abstract factory class, comprised of methods like ShouldHavePolice() and ShouldHaveCourts(). There may be several sub-classes like State1Rules, State2Rules etc. created that inheriting the class CentralGovernmentRules, and thus deriving its methods as well.

Note that the term “Factory” refers to the location in the code where the code is created.

A Factory Pattern is again an Object creation pattern. Here objects are created without knowing the class of the object. Sounds strange? Well, actually this means that the object is created by a method of the class, and not by the class’s constructor. So basically the Factory Pattern is used wherever sub classes are given the priviledge of instantiating a method that can create an object.

Describe the Builder Design Pattern

In a builder design pattern, an object creation process is separated from the object design construct. This is useful becuase the same method that deals with construction of the object, can be used to construct different design constructs.

What is the Lazy Design Pattern?

The approach of the Lazy Design Pattern is not to create objects until a specific requirement matches, and when it matches, object creation is triggered. A simple example of this pattern is a Job Portal application. Say you register yourself in that site thus filling up the registration table, only when the registration table is filled, the other objects are created and invoked, that prompt you to fill in other details too, which will be saved in other tables.

What is the Prototype Design Pattern?

A prototype design pattern relies on creation of clones rather than objects. Here, we avoid using the keyword ‘new’ to prevent overheads.

What is the Singleton Design Pattern?

The Singleton design pattern is based on the concept of restricting the instantiation of a class to one object. Say one object needs to perform the role of a coordinator between various instances of the application that depend on a common object, we may design an application using a Singleton. Usage of Singleton patterns is common in Banking, Financial and Travel based applications where the singleton object consists of the network related information.

A singleton class may be used to instantiate an object of it, only if that object does not already exist. In case the object exists, a reference to the existing object is given. A singleton object has one global point of access to it.

An ASP.NET Web Farm is also based on the Singleton pattern. In a Web Farm, the web application resides on several web servers. The session state is handled by a Singleton object in the form of the aspnet_state.exe, that interacts with the ASP.NET worker process running on each web server. Note that the worker process is the aspnet_wp.exe process. Imagine one of the web servers shutting down, the singleton object aspnet_state.exe still maintains the session state information across all web servers in the web farm.

In .NET, in order to create a singleton, a class is created with a private constructor, and a “static readonly” variable as the member that behaves as the instance.

What are Structural Design Patterns?

A structural design pattern establishes a relationship between entities. Thus making it easier for different components of an application to interact with each other. Following are some of the commonly known structural patterns:

>>> Adapter Pattern – Interfaces of classes vary depending on the requirement.
>>> Bridge Pattern – Class level abstraction is separated from its implementation.
>>> Composite Pattern – Individual objects & a group of objects are treated similarly in this approach.
>>> Decorator Pattern – Functionality is assigned to an object.
>>> Facade Pattern – A common interface is created for a group of interfaces sharing a similarity.
>>> Flyweight Pattern – The concept of sharing a group of small sized objects.
>>> Proxy Pattern – When an object is complex and needs to be shared, its copies are made. These copies are called the proxy objects.

What are the different types of Proxy Patterns?

1 – Remote Proxy – A reference is given to a different object in a different memory location. This may be on a different or a same machine.
2 – Virtual Proxy – This kind of object is created only & only when really required because of its memory usage.
3 – Cache Proxy – An object that behaves as a temporary storage so that multiple applications may use it. For example, in ASP.NET when a page or a user control contains the OutputCache directive, that page/control is cached for some time on the ASP.NET web server.

What is a behavioral design pattern?

Behaviorial design patterns focus on improving the communication between different objects. Following are different types of behavioral patterns:
>>> Chain Or Responsibilities Pattern – In this pattern, objects communicate with each other depending on logical decisions made by a class.
>>> Command Pattern – In this pattern, objects encapsulate methods and the parameters passed to them.
>>> Observer Pattern – Objects are created depending on an events results, for which there are event handlers created.

What is the MVC Pattern (Model View Controller Pattern)?

The MVC Pattern (Model View Controller Pattern) is based on the concept of designing an application by dividing its functionalities into 3 layers. Its like a triad of components. The Model component contains the business logic, or the other set of re-usable classes like classes pertaining to data access, custom control classes, application configuration classes etc. The Controller component interacts with the Model whenever required. The control contains events and methods inside it, which are raised from the UI which is the View component.

Consider an ASP.NET web application. Here, all aspx, ascx, master pages represent the View.

The code behind files (like aspx.cs, master.cs, ascx.cs) represent the Controller.

The classes contained in the App_Code folder, or rather any other class project being referenced from this application represent the Model component.

Advantages: * Business logic can be easily modified, without affecting or any need to make changes in the UI.
* Any cosmetic change in the UI does not affect any other component.

What is the Gang of Four Design Pattern?

The history of all design patterns used in modern day applications derive from the Gang of Four (GoF) Pattern. Gang of Four patterns are categorized into 3 types:
1 – Creational
2 – Structural
3 – Behavioral

The term “Gang of Four” (or “GoF” in acronym) is used to refer to the four authors of the book Design Patterns: Elements of Reusable Object-Oriented Software. The authors are Erich Gamma, Ralph Johnson, Richard Helm and John Vlissides.

When should design patterns be used?

While developing software applications, sound knowledge of industry proven design patterns make the development journey easy and successful. Whenever a requirement is recurring, a suitable design pattern should be identified. Usage of optimal design patterns enhance performance of the application. Though there are some caveats. Make sure that there are no overheads imposed on a simple requirement, which means that design patterns should not be unnecessarily be used.

How many design patterns can be created in .NET?

As many as one can think. Design patterns are not technology specific, rather their foundation relies on the concept of reusability, object creation and communication. Design patterns can be created in any language.

 

 

http://www.dotnetuncle.com/Design-Patterns/dot-net-design-pattern-interview-questions.aspx

How to remove duplicate from string array in .net

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In one case i have to right a method to remove duplication from array of strings. 
i write this code 

Public Function RemoveDuplicates(ByVal items As String()) As String()
    Dim noDupsArrList As New ArrayList()
    For i As Integer = 0 To items.Length - 1
        If Not noDupsArrList.Contains(items(i).Trim()) Then
            noDupsArrList.Add(items(i).Trim())
        End If
    Next
    
    Dim uniqueItems As String() = New String(noDupsArrList.Count - 1) {}
    noDupsArrList.CopyTo(uniqueItems)
    Return uniqueItems
End Function

How to filter uploader control using client side script in asp.net

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For any client side action we have to choose a scripting language to build our logic. Let us go for JavaScript. When use a file control we have to use a button control for doing the uploading action. It is better to refer to Anand’s article CodeSnip: Working with FileUpload Control to get the basic idea of using FileUpload control.

Then at the button Client event we have to add some JavaScript action to do the filtering action. We have to use the “OnClientClick” event of a <asp:Button /> control. The code is given below.

Listing 2: OnClientClick

<asp:Button ID="btnUpload" runat="server" OnClick="btnUpload_Click" Text="Upload"
Width="64px" OnClientClick="return CheckForTestFile();" />

Now our objective is to put the filtering logic in CheckForTestFile() JavaScript function. For this action, copy and paste the following code inside your <HEAD> tag of aspx page.

Listing 3: JS Filter function

<script language="javascript">  
  //Trim the input text
  function Trim(input)
  {
    var lre = /^s*/; 
    var rre = /s*$/; 
    input = input.replace(lre, ""); 
    input = input.replace(rre, ""); 
    return input; 
   }
 
   // filter the files before Uploading for text file only  
   function CheckForTestFile() 
   {
        var file = document.getElementById('<%=fileDocument.ClientID%>');
        var fileName=file.value;        
        //Checking for file browsed or not 
        if (Trim(fileName) =='' )
        {
            alert("Please select a file to upload!!!");
            file.focus();
            return false;
        }
 
       //Setting the extension array for diff. type of text files 
       var extArray = new Array(".txt", ".doc", ".rtf", ".pdf", ".sxw", ".odt", 
                                ".stw", ".html", ".htm", ".sdw", ".vor");      
 
       //getting the file name
       while (fileName.indexOf("") != -1)
         fileName = fileName.slice(fileName.indexOf("") + 1);
 
       //Getting the file extension                     
       var ext = fileName.slice(fileName.indexOf(".")).toLowerCase();
 
       //matching extension with our given extensions.
       for (var i = 0; i < extArray.length; i++) 
       {
         if (extArray[i] == ext) 
         { 
           return true;
         }
       }  
         alert("Please only upload files that end in types:  " 
           + (extArray.join("  ")) + "nPlease select a new "
           + "file to upload and submit again.");
           file.focus();
           return false;                
   }    
</script>

Let us go through the codes. The Trim() function would trim the input text. Therefore, in the above code we first check whether there is any file selected in FileUpload control or not. Then we parse the file name with the path to the file-name of the input file using the slice() method of JavaScript which takes the index as input. After getting the file we will still continue parsing to get the file extension out from the File name. Then we iterate a loop to match the input extension with the defeat extensions of our interest stored in an array. If the input extension does not match with any one of the given extension,s we show the alert message and return false as status. This does not allow us to Upload the file and give us a alert message to fetch a file with the given extensions.

 

reference : http://aspalliance.com/1614_Adding_Filter_Action_to_FileUpload_Control_of_ASPNET_20.1

How to get relative path for images in asp.net

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One common problem developers face  while using master page that images did not get proper path, there are many ways to do this. But best way to use  ResolveClientUrl . For example :

<img src=”<%= ResolveClientUrl(”images/disco_night.png”)%>” alt=”Disco night” />

after rendering  it converted it as

<img src=”../images/disco_night.png” mce_src=”../images/disco_night.png” alt=”Disco night” />

How to write word document in asp.net

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You can add follwing code at page level function and called in button or page load

function Void GenerateWordDoc()

{

string strDocBody;

try

{

strDocBody = “<html “ + “xmlns:o=’urn:schemas-microsoft-com:office:office’ “ + “xmlns:w=’urn:schemas-microsoft-com:office:word'” + “xmlns=’http://www.w3.org/TR/REC-html40′>” + “<head>” + “<title>Dynamic Generated Document</title>”;

strDocBody = strDocBody + “<!–[if gte mso 9]>” + “<xml>” + “<w:WordDocument>” + “<w:View>Print</w:View>” + “<w:Zoom>100</w:Zoom>” + “<w:DoNotOptimizeForBrowser/>” + “</w:WordDocument>” + “</xml>” + “<![endif]–>”;

strDocBody = strDocBody + “<style> @page” + “{size:8.5in 11.0in; mso-first-footer:ff1; mso-footer: f1; mso-header: h1; border:solid navy 2.25pt; padding:24.0pt 24.0pt 24.0pt 24.0pt;” + ” margin:0.75in 0.50in 0.75in 0.50in ; “ + ” mso-header-margin:.5in; “ + ” mso-footer-margin:.5in; mso-paper-source:0;}” + ” div.Section1″ + ” {page:Section1;}” + “p.MsoFooter, li.MsoFooter, div.MsoFooter{margin:0in; margin-bottom:.0001pt; mso-pagination:widow-orphan; tab-stops:center 3.0in right 6.0in; font-size:12.0pt; font-family:’Arial’;}” + “p.MsoHeader, li.MsoHeader, div.MsoHeader {margin:0in; margin-bottom:.0001pt; mso-pagination:widow-orphan; tab-stops:center 3.0in right 6.0in; font-size:12.0pt; font-family:’Arial’;}” + “–>” + “</style>” + “</head>”;

strDocBody = strDocBody + “<body lang=EN-US style=’tab-interval:.5in’>”;

//Users Content in which he want to show in word doc , in my case i call a function GetData which return string from database

strDocBody += GetData();

strDocBody += “</div> </body> </html> “;

//Force this content to be downloaded as a Word document

Response.AddHeader(“Content-Type”, “application/msword”);

Response.AddHeader(“Content-disposition”, “attachment; filename=mydoc.doc”);

Response.Charset = “”; Response.Write(strDocBody);

}

catch (Exception ex)

{

Response.Write(ex.Message);

}

}

 

How to get Ip of Url in c#

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Here is sample code  remember to add system.net namespace

IPHostEntry ip = Dns.GetHostByName (“www.yahoo.com”);
IPAddress [] IpA = ipE.AddressList;
for (int i = 0; i < IpA.Length; i++)
{
    Console.WriteLine (“IP Address {0}: {1} “, i, IpA[i].ToString ());
}

How to access detailed information of a visitor in asp.net

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In ASP.NET, the Request.ServerVariables collection holds a lot of useful information about the visitor.

For example:

// Getting ip of visitor
string ip = Request.ServerVariables[“REMOTE_ADDR”];
// Getting the page which called the script
string page = Request.ServerVariables[“HTTP_REFERER”];
// Getting Browser Name of Visitor
if (Request.ServerVariables[“HTTP_USER_AGENT”].Contains(“MSIE”))
  browser = “Internet Explorer”;
if (Request.ServerVariables[“HTTP_USER_AGENT”].Contains(“FireFox”))
  browser = “Fire Fox”;
if (Request.ServerVariables[“HTTP_USER_AGENT”].Contains(“Opera”))
  browser = “Opera”;

How do I find difference between two dates? In C#

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DateTime startDate = new DateTime(2005, 2, 1, 3, 4, 12, 56);
// End date
DateTime endDate = new DateTime(2005, 12, 12, 4, 30, 45, 12);
// Time span
TimeSpan diffDate = endDate.Subtract ( startDate );
// Spit it out
Response.Write( “Time Difference: <br/> “);
Response.Write(diffDate.Days.ToString() + ” Days <br/>”);
Response.Write(diffDate.Hours.ToString() + ” Hours <br/>” );
Response.Write(diffDate.Minutes.ToString() + ” Minutes <br/>”);
Response.Write(diffDate.Seconds.ToString() + ” Seconds <br/> “);
Response.Write(diffDate.Milliseconds.ToString() + ” Milliseconds <br/>”);

Compiler Error Message: CS0030: Cannot convert type ‘ASP.login_aspx’ to ‘System.Web.UI.WebControls.Login’

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Problem occur when you page name is same as Class in .net
Usually we develop the login page as login.aspx . When we publish it, the aspx is retained and tries to compile against Login’s codebehind,  which is not resolve properly in the assembly due to System.Web.Login.
To avoid it developer must Insure that Page name will not the same as in System.Web.

how to upload larger files in asp.net 2

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by default asp.net application did not upload file more than 4.5 mb or 4 mb. For this purpose You have to add following http runtime tag in web.cofig of web site.

<httpRuntime executionTimeout=“90“ maxRequestLength=“20096“useFullyQualifiedRedirectUrl=“false“ minFreeThreads=“8“ minLocalRequestFreeThreads=“4“appRequestQueueLimit=“10000“;/>

you have to change two setting in above code.MaxRequestLength (Here you mention the size limit of file , bydefault it is 4 mb) and appRequestQueueLimit (it is the time when application take time to upload the request.)