Expiring a page on clicking browser back button in Asp.net?

It is most common in some scenarios for us to expire a page as soon as the user clicks the back button in the web browser. This will be needed in scenarios like, when registering a new user or company in our web application.


For all who need this, I thought of sharing the code which will accomplish the same.


Response.Expires = -1;
Response.Cache.SetNoServerCaching();
Response.Cache.SetAllowResponseInBrowserHistory(false);
Response.CacheControl ="no-cache";
Response.Cache.SetNoStore();


Just paste the above code in the Page_Load event of your asp.net web page for which you want to expire when user clicks browser back button.

How to find the port no of SQL server instance?

The default port of SQL server instance will be normally 1433, for more information please refer the below link


http://support.microsoft.com/kb/287932

But It is not necessary that the SQL server instance will operate in the default port in all client places .You can find the port of SQL server 2008 instance by going to .Start->programs->Microsoft SQL Server 2008 R2->Configuration Tools->SQL Server Configuration Manager.

In SQL Server Configuration Manager go to, SQL Server Network Configuration->protocols for MSQLSERVER->double click TC/IP.

Please refer the below link for more options

http://decipherinfosys.wordpress.com/2008/01/02/finding-the-port-number-for-a-particular-sql-server-instance/
Please see the screen shot below for more details

What will happened if continue statement is placed in a for Loop?

What will happened if continue statement is placed in a for Loop?


Continue statement is used in c# to set control to the beginning of the loop.

namespace ConsoleApplication1
{
class Program
{
static void Main(string[] args)
{
for (int i = 0; i <= 10; i++)
{
Console.WriteLine (i.ToString());
continue;
Console.WriteLine("Iam never printed");
}
}
}
}

For example in the below code the line Console.WriteLine("Iam never printed"); is never executed because the control is set back to the beginning of the loop when the execution reaches the continue; stetment.

Create your Business Object using SQL Query?

Today I was designing my application and I need to write about 30 classes as the business object layer. As per my design, the business objects in my application are exact replica of my databases table. In order to save time in writing these classes I came up with a tricky logic using SQL server query .I thought of putting in this; in my blog, as it may help some others who needs to do a same exercises.


For your reference please find below a sample of my table ('CountryMaster') in databases

Ignored to write the C# business objects, I used the below query which will gives me the property entry’s for my business objects class.

select 'public '+
case when system_type_id=56 then ' int '+sys.columns.name+' { get; set; }'
when system_type_id=167 then ' string '+sys.columns.name+' { get; set; }'
when system_type_id=239 then ' string '+sys.columns.name+' { get; set; }'
when system_type_id=231 then ' string '+sys.columns.name+' { get; set; }'
when system_type_id=104 then ' string '+sys.columns.name+' { get; set; }'
when system_type_id=61 then ' DateTime '+sys.columns.name+' { get; set; }'
when system_type_id=108 then ' double '+sys.columns.name+' { get; set; }'
when system_type_id=175 then ' string '+sys.columns.name+' { get; set; }'
when system_type_id=34 then ' byte[] '+sys.columns.name+' { get; set; }'
when system_type_id=99 then ' string '+sys.columns.name+' { get; set; }'
end AS 'Class Properties'
from sys.columns
inner join sys.tables on sys.tables.name='CountryMaster'
where sys.columns.object_id=sys.tables.object_id

 
On running the above query will be getting the entry for my business object as below.

Note: the above query may not be complete for all SQL data types, If your databases is having more data types columns, the please add the appropriate c# equal ant code in the case statements.

copy the results from SQL and paste in your C#.net projects in the corresponding class file as  below.

using System;

using System.Collections.Generic;
using System.Linq;
using System.Text;
///

/// Business Objects Class
///

/// Rajesh Kamalakshan
/// 16-12-2011
namespace FiesPackage.Country.BusinessObjects
{
public class Country
{
public int CountryId { get; set; }
public string CountryCode { get; set; }
public string CountryName { get; set; }
public string InBuilt { get; set; }
public int CompanyId { get; set; }
public string Misc { get; set; }
}
}

The highlighted portion has been pasted from the SQL result using the above query.

Type initializer for threw an exception


I thought of sharing this information to others as  it may help someone having the same issues .I have an application which is done in vb .net . It works fine when run from source. This application is a dll bases and it uses crystal report. Everything worked fine with the source.

But the real problem started when I compiled the source to exe and dll .In the compiled version whenever a dll in this application is called form an exe it was throwing an exception as “type initializer for threw an exception”, I googled a lot and found that this issues is due to missing of crystal report files in the clinet machine or Live Pc.

Note: This error can also happed due to some missing files, in my case it was Crystal reports’s supporting files. You can get more details about the missing reference from the stack trace which will be available in the exception.

The solution for this issue was to download and apply the crystal Report redistributable pack, which is relevant for your OS platform where the Application is running. We can get these packs from the below site of crystal report.

http://resources.businessobjects.com/support/additional_downloads/runtime.asp#09

Since my application was compiled in VS 2008, i downloaded the Crystal Reports Basic for Visual Studio .NET 2008

As per the version of crystal report used in your application ,you have to download the respective redistributable package.

Reverse percentage calculation?

How to find X, which give you 115000 when 15% is deducted(Reverse Percentage Calculation)?

eg ax + bx = c your eqution is
ax +b = c
where a , b and c are numerical values and x is the unknown!

For the time being we can phrase the equation as

x - 15%x = 115000

then your answer would be

x(1 - 0.15) = 115000 (factorizing x)

x (0.85) = 115000 then dividing by 0.85

x = 135294.1176

substitute for x and you will find this is a correct answer!

135294.1176 - 0.15(135294.1176) = 115000


http://uk.answers.yahoo.com/question/index?qid=20070420010452AAsnX7C

How to bring jQuery Intellisense in VS 2008

First run the hopfix VS90SP1-KB958502-x86 for VS 2008,you can find the hot fix at


http://archive.msdn.microsoft.com/KB958502/Release/ProjectReleases.aspx?ReleaseId=1736

Open Visual Studio 2008 > File > New > Website > Choose ‘ASP.NET 3.5 website’ from the templates > Choose your language (C# or VB) > Enter the location > Ok. In the Solution Explorer, right click your project > New Folder > rename the folder as ‘Scripts’

Right click the Scripts folder > Add Existing Item > Browse to the path where you downloaded the jQuery library (jquery-1.2.6-vsdoc.js) and the intellisense documentation (jquery-1.2.6-vsdoc.js) > Select the files and click Add.

Now drag and drop the jquery-1.2.6.js file from the Solution Explorer on to your page to create a reference

You can dounload Jquerry intellisense documentation for Vs2008 (jquery-1.2.6-vsdoc.js) at
http://code.google.com/p/jqueryjs/downloads/detail?name=jquery-1.2.6-vsdoc.js

You can dounload Jquerry jQuery library (jquery-1.2.6-vsdoc.js) at
http://code.google.com/p/jqueryjs/downloads/detail?name=jquery-1.2.6.js

Note: Since you have applied the hotfix, you do not have to manually add a reference to the jquery-1.2.6-vsdoc.js file in your page. Once the reference to the runtime library has been added, Visual Studio automatically searches for the ‘vsdoc’ file and loads it. You just need to keep both the runtime library and the documentation file next to each other

To test intellisense, add a  script block and key in ‘$(‘. 


More infomrtaion regarding the same can be found at the below loaction

http://weblogs.asp.net/scottgu/archive/2008/11/21/jquery-intellisense-in-vs-2008.aspx
or
http://www.dotnetcurry.com/ShowArticle.aspx?ID=231