ADO.NET (ActiveX Data Objects .NET) ek data access technology hai jo .NET framework mein use hoti hai. Iska main purpose database se data ko retrieve, manipulate aur update karna hota hai. ADO.NET ka use SQL Server ya kisi bhi relational database ko access karne ke liye kiya jata hai.

Ismein kuch important components hote hain:

  1. Connection: Ye database se connection establish karne ka kaam karta hai. Jaise SqlConnection object SQL Server ke liye.
  2. Command: Ye SQL queries ko execute karta hai. Jaise SqlCommand object.
  3. DataReader: Ye forward-only, read-only record set return karta hai. Matlab aap ek baar data read kar sakte hain aur phir usse change nahi kar sakte.
  4. DataAdapter: Ye data ko database aur in-memory data set ke beech transfer karta hai. Matlab ye data ko read karta hai aur usse DataTable ya DataSet mein store karta hai.
  5. DataSet: Ye ek in-memory representation hota hai jo tables, rows, aur relationships ko store karta hai.

ADO.NET ko use karke aap apne applications mein data-driven features implement kar sakte hain jaise ki database se data fetch karna, update karna, delete karna, etc.

Iska advantage ye hai ki ye disconnected environment mein bhi kaam karta hai, yani aap database se connection close karke bhi data manipulate kar sakte hain, jab tak aapke paas DataSet ya DataReader ka data ho.

ADO.NET ka ek simple example dekhte hain jisme hum ek SQL Server database se data retrieve karenge aur display karenge. Is example mein hum SqlConnection, SqlCommand, aur SqlDataReader ka use karenge.

Scenario:

Maan lijiye humare paas ek database hai jiska naam SchoolDB hai aur usmein ek table Students hai, jisme student ke details stored hain (id, name, age).

1. Database Structure:

    CREATE TABLE Students (
        StudentID INT PRIMARY KEY,
        StudentName VARCHAR(100),
        Age INT
    );

2. C# Code Example using ADO.NET:

    using System;
    using System.Data.SqlClient;

    class Program
    {
        static void Main()
        {
            // Database connection string
            string connectionString = "Server=localhost;Database=SchoolDB;Integrated Security=True;";

            // SQL query to fetch data from Students table
            string query = "SELECT StudentID, StudentName, Age FROM Students";

            // Creating connection to the database
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                // Opening the connection
                connection.Open();

                // Creating command object
                SqlCommand command = new SqlCommand(query, connection);

                // Executing the command and using DataReader to read the result
                using (SqlDataReader reader = command.ExecuteReader())
                {
                    // Checking if there are any rows to read
                    if (reader.HasRows)
                    {
                        Console.WriteLine("Student Details:");
                        while (reader.Read())  // Reading data row by row
                        {
                            // Fetching values from each column by index
                            int studentID = reader.GetInt32(0);
                            string studentName = reader.GetString(1);
                            int age = reader.GetInt32(2);

                            // Displaying data
                            Console.WriteLine($"ID: {studentID}, Name: {studentName}, Age: {age}");
                        }
                    }
                    else
                    {
                        Console.WriteLine("No records found.");
                    }
                }
            }

            // End of the program
            Console.WriteLine("Press any key to exit.");
            Console.ReadKey();
        }
    }

Explanation:

  1. Connection: Hum SqlConnection object banate hain, jo database se connection establish karta hai. Yahan hum connection string mein server address, database ka naam, aur authentication method specify karte hain.

  2. Command: Hum SqlCommand object banate hain jisme SQL query (SELECT query) hoti hai jo Students table se data fetch karne ke liye hoti hai.

  3. DataReader: SqlDataReader ka use hum data ko read karne ke liye karte hain. ExecuteReader() method query ko execute karta hai aur result ko SqlDataReader object mein store karta hai.

  4. Reading Data: reader.Read() method ko use karte hain, jo data ko row by row fetch karta hai. Hum reader.GetInt32(0), reader.GetString(1), etc., se column values ko fetch karte hain.

  5. Display: Finally, hum Console.WriteLine() ke through fetched data ko print karte hain.

Output Example:

Maan lijiye table Students mein ye data hai:

StudentIDStudentNameAge
1John18
2Sarah19
3Mike20





To output screen par ye display hoga:

    Student Details:
    ID: 1, Name: John, Age: 18
    ID: 2, Name: Sarah, Age: 19
    ID: 3, Name: Mike, Age: 20
    Press any key to exit.

Summary:

Is example mein humne ADO.NET ka use karke ek SQL Server database se data retrieve kiya aur display kiya. Ye ek basic example hai jisme humne SqlConnection, SqlCommand, aur SqlDataReader ka use kiya.

Leave a Reply

Your email address will not be published. Required fields are marked *


Talk to us?

Post your blog

F.A.Q

Frequently Asked Questions