This contains the basic objects used for accessing and storing relational data, such as

DataSet,DataTable, and DataRelation. Each of these is independent of the type of data

source and the way we connect to it.

2. System.Data.OleDB

It contains the objects that we use to connect to a data source via an OLE-DB provider,

such as OleDbConnection, OleDbCommand, etc. These objects inherit from the common

base classes, and so have the same properties, methods, and events as the SqlClient

equivalents.

3. System.Data.SqlClient

This contains the objects that we use to connect to a data source via the Tabular Data

Stream (TDS) interface of Microsoft SQL Server (only). This can generally provide better performance as it removes some of the intermediate layers required by an OLE-DB

connection.

4. System.XML

This Contains the basic objects required to create, read, store, write, and manipulate

2). Can you give a overview of ADO.NET architecture ?

5). What are major difference between classic ADO and ADO.NET ?

Following are some major differences between both

√ As in classic ADO we had client and server side cursors they are no more

present in ADO.NET. Note it's a disconnected model so they are no more

applicable.

√ Locking is not supported due to disconnected model.

√ All data persist in XML as compared to classic ADO where data

6). What is the use of connection object ?

They are used to connect a data to a Command object.

√ An OleDbConnection object is used with an OLE-DB provider255

√ A SqlConnection object uses Tabular Data Services (TDS) with MS SQL Server

7). What is the use of command objects ?

8). What is the use of dataadapter ?

These are objects that connect one or more Command objects to a Dataset object. They

provide logic that would get data from the data store and populates the tables in the

DataSet, or pushes the changes in the DataSet back into the data store.

√ An OleDbDataAdapter object is used with an OLE-DB provider

√ A SqlDataAdapter object uses Tabular Data Services with MS SQL Server.

using System;

using System.Data;

using System.Configuration;

using System.Web;

using System.Web.Security;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Web.UI.WebControls.WebParts;

using System.Web.UI.HtmlControls;

///

/// Summary description for mark

///

public class mark

{

public mark()

{

//

// TODO: Add constructor logic here

//

}

private string[] x = new string[5];

public string this [int index]

{

get

{

return x[index];

}

set

{

x[index] = value;

}

}

}

Execute in page load event in the page

//Output: 22-06-2007 00:00:00

//Examples for DateTime Manipulation in .Net
//Example 1 : Adding Minutes to Current Date.
dt1 = dt1.AddMinutes(5.0);
Response.Write(dt1.ToString() + "
");
//Output: 22-06-2007 00:05:00

//Example 2 : Adding Seconds to DateTime Object., similarly you can add milliseconds
dt1 = dt1.AddSeconds(30.0);
Response.Write(dt1.ToString() + "
");
//Output: 22-06-2007 00:05:30

//Example 3 : Adding Hours to DateTime Object in .Net.
dt1 = dt1.AddHours(5.0);
Response.Write(dt1.ToString() + "
");
//Output: 22-06-2007 05:05:30

//Example 4 : Adding Time to DateTime Object.
//You can replace Example 1,2 and 3 by simply adding TimeSpan with your desired
//TimeSpan value.
//Here we are adding 5 Hours, 5 Minutes and 30 Seconds.
dt1 = dt1.Add(new TimeSpan(5,5,30));
Response.Write(dt1.ToString() + "
");
//Output: 22-06-2007 10:11:00

//Example 5 : Adding Days to DateTime Object in .Net
dt2 = dt1.AddDays(7.0); //Initializing dt2 object with 7 days ahead from
//dt1 DateTime value.
Response.Write(dt2.ToString() + "
");
//Output: 29-06-2007 10:11:00

//Example 6 : Adding Month to DateTime Object
dt2 = dt2.AddMonths(1);
Response.Write(dt2.ToString() + "
");
//Output: 29-07-2007 10:11:00

//Example 7 : Adding Year to DateTime Object
dt2 = dt2.AddYears(1);
Response.Write(dt2.ToString() + "
");
//Output: 29-07-2008 10:11:00


//Examples of Retrieving DateTime object value.
//Example 1 : Get Day value.
int intDay = dt1.Day;
Response.Write(intDay.ToString() + "
");
//Output: 22

//Example 2 : Get Day of Week.
DayOfWeek dow = dt1.DayOfWeek;
Response.Write(dow.ToString() + "
");
//Output: Friday
//How to find whether day of week is sunday or saturday?
if(dow == DayOfWeek.Sunday dow == DayOfWeek.Saturday)
{
//Hurray its weekend.
}

//Example 3 : Get the Day of Year
int intYear = dt1.DayOfYear; //Similarly you can get Year value.
Response.Write(intYear.ToString() + "
");
//Output: 173


//Similarly you can get Hours, Minutes, Seconds, Milliseconds value.



//Conversion of String to DateTime
//Make use of Parse Method of DateTime to "Convert String to DateTime in .Net"
DateTime dt4 = DateTime.Parse("08/06/2007");
DateTime dt5 = DateTime.Parse("10/06/2007");

//Comparing Date
//How to Find whether both dates are equal or Not?
//How to compare two dates in .Net?
if (DateTime.Compare(dt4, dt5) == 0)
{
Response.Write("Both Dates are Equal" + "
");
}
else if (DateTime.Compare(dt4, dt5) < 0) { Response.Write(dt4.ToString() + " is Less than " + dt5.ToString() + "
");
}
else
{
Response.Write(dt4.ToString() + " is Greater than "
+ dt5.ToString() + "
");
}
//Output: 08-06-2007 00:00:00 is Less than 10-06-2007 00:00:00
/*Note: You may recieve error: "String was not recognized as a valid
DateTime." This may be occur as in India the DateTime format is followed
as "dd/mm/yyyy" But let say if you are in USA than it follow "mm/dd/yyyy" so here
there is crash situation and so you might recieve above error, so to avoid such
error make sure that user input valid date before you Parse date. */


//Difference between Date
//How to Find difference between two dates in .Net?
//How to Find days difference between two dates in .Net?
//How to subtract one date from another?
TimeSpan tsDiff = dt5.Subtract(dt4); //Note: Always subtract smaller date
//value from greater date
Response.Write("Difference between " + dt4.ToString() + " and " +
dt5.ToString() + " is " + tsDiff.Days.ToString() + " days." + "
");
//Output: Difference between 08-06-2007 00:00:00 and 10-06-2007 00:00:00 is 2 days.


//Similarly you can also find:
//How many hour difference between two dates
//How many seconds difference between two dates
//And so on... by changing tsDiff property value to hours, seconds....
//instead of tsDiff.Days.


//Compare Time
//How to Find whether both Time are equal or Not?
//How to compare Time in .Net?
dt4 = DateTime.Parse("4:30 AM");
dt5 = DateTime.Parse("7:30 PM");
if (DateTime.Compare(dt4, dt5) == 0)
{
Response.Write("Both Times are Equal" + "
");
}
else if (DateTime.Compare(dt4, dt5) < 0) { Response.Write(dt4.ToShortTimeString() + " is Less than " + dt5.ToShortTimeString() + "
");
}
else
{
Response.Write(dt4.ToShortTimeString() + " is Greater than "
+ dt5.ToShortTimeString() + "
");
}
//Output: 04:30:00 is Less than 19:30:00


//Difference between Time
//How to Find difference between two Time value in .Net?
//How to Find Hours difference between two Time in .Net?
//How to subtract one Time from another?
//How to find elapsed Time between Two Time value in .Net?
tsDiff = dt5.Subtract(dt4); //Note: Always subtract smaller date
//value from greater date
Response.Write("Difference between " + dt4.ToString() + " and " + dt5.ToString() + " is " + tsDiff.Hours.ToString() + " Hours." + "
");
//Output: Difference between 22-06-2007 04:30:00 and 22-06-2007 19:30:00 is 15 Hours.


//More on DateTime
//How many days in a given month in .Net?
int intDaysInMonth = DateTime.DaysInMonth(2007, 6); //Pass valid year, and month
Response.Write(intDaysInMonth.ToString() + "
");
//Output: 30

//How to find whether given year is Leap year or not in .Net?
Response.Write( DateTime.IsLeapYear(2007)); //Pass valid year
//Output: False

//How to find current date and time?
Response.Write("Current Date and Time: " + DateTime.Now + "
");
//Output: Current Date and Time: 22-06-2007 11:31:04

//How to find current date?
Response.Write("Current Date: " + DateTime.Today + "
");
//Output: Current Date: 22-06-2007 00:00:00