Asp.net custom error page

ASP.NET provides a simple yet powerful way to deal with errors that occur in your web applications. We will look at several ways to trap errors and display friendly meaningful messages to users. We will then take the discussion a step further and learn how to be instantly notified about problems so you can cope with them right away. As a geek touch we will also track the path 404's travel.

In the days of "classic" ASP you used to get cryptic—an often times downright misleading—error messages. "White pages" leave your visitors in the dark who don't know what happened and what to do next besides closing the browser or navigating away.
It's obvious that "white pages" are ugly but there's another angle to this—ASP.NET displays an exception stack trace which may reveal what your code does and how it works. These days, when the word "security" is in vogue, this could be a dangerous side effect.
Custom error pages are not luxury any more, they are a must-have. You have several ways to implement them.

Every time you create a web form in Visual Studio .NET you see that your page class derives from System.Web.UI.Page. The Page object helps you trap page-level errors. For this to happen you need to override its OnError method as follows:

protected override void OnError(EventArgs e)
{
  // At this point we have information about the error
  HttpContext ctx = HttpContext.Current;

  Exception exception = ctx.Server.GetLastError ();

  string errorInfo = 
     "<br>Offending URL: " + ctx.Request.Url.ToString () +
     "<br>Source: " + exception.Source + 
     "<br>Message: " + exception.Message +
     "<br>Stack trace: " + exception.StackTrace;

  ctx.Response.Write (errorInfo);

  // --------------------------------------------------
  // To let the page finish running we clear the error
  // --------------------------------------------------
  ctx.Server.ClearError ();
 
  base.OnError (e);
}

What is RDBMS?

Relational Data Base Management Systems (RDBMS) are database management systems that maintain data records and indices in tables. Relationships may be created and maintained across and among the data and tables. In a relational database, relationships between data items are expressed by means of tables. Interdependencies among these tables are expressed by data values rather than by pointers. This allows a high degree of data independence. An RDBMS has the capability to recombine the data items from different files, providing powerful tools for data usage.

OnClientClick Event In Asp.net

OnClientClick ="javascript:if (confirm('Are You Sure you want to delete?')==false)return false;"

Delete All Stored Procedures

declare @procName varchar(500)
declare cur cursor
    for select [name] from sys.objects where type = 'p'
open cur

fetch next from cur into @procName
      while @@fetch_status = 0
      begin
            if @procName <> 'DeleteAllProcedures'
                  exec('drop procedure ' + @procName)
                  fetch next from cur into @procName
      end

close cur
deallocate cur

Delete All Views

declare @procName varchar(500)
declare cur cursor
    for select [name] from sys.objects where type = 'v'
open cur

fetch next from cur into @procName
      while @@fetch_status = 0
      begin
                  exec('drop view ' + @procName)
                  fetch next from cur into @procName
      end
close cur
deallocate cur

Delete All Functions

declare @procName varchar(500)
declare cur cursor
    for select [name] from sys.objects where type = 'fn'
open cur

fetch next from cur into @procName
      while @@fetch_status = 0
      begin
                  exec('drop function ' + @procName)
                  fetch next from cur into @procName
      end

close cur
deallocate cur

Delete All Tables in Sql

--Delete All Keys

DECLARE @Sql NVARCHAR(500) DECLARE @Cursor CURSOR
SET @Cursor = CURSOR FAST_FORWARD FOR
SELECT DISTINCT sql = 'ALTER TABLE [' + tc2.TABLE_NAME + '] DROP [' + rc1.CONSTRAINT_NAME + ']'
FROM INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS rc1
LEFT JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS tc2 ON tc2.CONSTRAINT_NAME =rc1.CONSTRAINT_NAME
OPEN @Cursor FETCH NEXT FROM @Cursor INTO @Sql
WHILE (@@FETCH_STATUS = 0)
BEGIN
Exec SP_EXECUTESQL @Sql
FETCH NEXT FROM @Cursor INTO @Sql
END
CLOSE @Cursor DEALLOCATE @Cursor
GO
EXEC sp_MSForEachTable 'DROP TABLE ?'
GO

Inheritance and Cascading Styles in CSS Explained

1. Styles can be inherited from a parent

Some styles, like font family, text-alignment etc., are automatically inherited by child elements from their parent element (i.e. by an element contained inside another one).
Others are not automatically inherited.

Example

<div style=”font-family:serif; border:1px solid red; padding:10px;”>

This text will be in a serif font.
<p>
This text is also in a serif font, because font is inherited by default.
But the border and padding properties are not inherited from the parent div.
</p>

</div>

However, you can make an element inherit styles from its parent.

Example

<div style=”font-family:serif; border:1px solid red; padding:10px;”>

This text will be in a serif font.
<p style=”border:inherit;”> 

Now the paragraph also has a red border.
Border properties are not inherited by children, by default, but because I set border to “inherit”, it is.

</p>

</div>

css : Avoid Superfluous Selectors

Sometimes your CSS declaration can be simpler, meaning if you find yourself coding the following:

• ul li { ... }
• ol li { ... }
• table tr td { ... }

They can be shorten down to just

• li { ... }
• td { ... }

Explanation:
li will only exist within ul or ol
and td will only be inside
tr and tableso there’s really not necessary to re-insert them.

Use Shorthand CSS

Shorthand CSS gives you a shorter way of writing your CSS codes, and most important of all – it makes the code clearner and easier to understand.

Instead of creating CSS like this

.header{
background-color: #fff;
background-image: url(image.gif);
background-repeat: no-repeat;
background-position: top left;
}
It can be short-handed into the following:

.header {
background: #fff url(image.gif) no-repeat top left
}

CSS3 Borders

CSS3 Borders

With CSS3, you can create rounded borders, add shadow to boxes,
and use an image as a border - without using a design program, like Photoshop.

In this Post you will learn about the following border properties:
border-radius
box-shadow
border-image
Browser Support
Internet Explorer 9 supports some of the new border properties.

Firefox requires the prefix -moz- for border-image.

Chrome and Safari requires the prefix -webkit- for border-image.

Opera requires the prefix -o- for border-image.

Safari also needs the prefix -webkit- for box-shadow.

Opera supports the new border properties.

CSS3 Rounded Corners
div
{
border:2px solid;
border-radius:25px;
-moz-border-radius:25px; /* Firefox 3.6 and earlier */
}
CSS3 Box Shadow
div
{
box-shadow: 10px 10px 5px #888888;
-webkit-box-shadow: 10px 10px 5px #888888; /* Safari */
}
CSS3 Border Image
div
{
border-image:url(border.png) 30 30 round;
-moz-border-image:url(border.png) 30 30 round; /* Firefox */
-webkit-border-image:url(border.png) 30 30 round; /* Safari and Chrome */
-o-border-image:url(border.png) 30 30 round; /* Opera */
}

Threading

(1)What is Multi-tasking ?
It’s a feature of modern operating systems with which we can run multiple programs a
same time example Word, Excel etc.

(2)What is Multi-threading ?
Multi-threading forms subset of Multi-tasking. Instead of having to switch between
programs this feature switches between different parts of the same program. Examp
you are writing in word and at the same time word is doing a spell check in backgroun

(3)What is a Thread ?
A thread is the basic unit to which the operating system allocates processor time.
(4)Did VB6 support multi-threading ?
While VB6 supports multiple single-threaded apartments, it does not support a fre
threading model, which allows multiple threads to run against the same set of data.