How to Create Database Connection in Asp.Net

To make dynamic website,portals and online application, we require database (SQL Server,Access,MySQL,Oracle) etc.

To create a database connection in asp.net follow the following steps:-

1. By using Web.config:-

(i) Go to your web.config file and then locate the <connectionStrings/>.

Change it like this:-

<connectionStrings>                              
<add name="con" connectionString="Data Source=.; Initial Catalog=test;Integrated Security=True"/>
</connectionStrings>

in this Data Source stand for server where your database resides. . stand for local server. Initial catalog stand for database name.

(ii) Now come to your coding page(demo.aspx.cs) .

Add the following Namespace :-

 using System.Data.SqlClient;
using System.Configuration;

Now initialize connection on page_load or button click event wherever you want.

string strcon = ConfigurationManager.ConnectionStrings["con"].ConnectionString; SqlConnection conn = new SqlConnection(strcon);
conn.open();

2. Directly on code file.

Add the following Namespace :-

 using System.Data.SqlClient;
using System.Configuration;

SqlConnection con = new SqlConnection("Server=Youserver name or comp name;Database=databasename;Trusted_Connectopn=True"); SqlCommand cmd = new SqlCommand("Write your sql query here eg. select * from Table name");   
con.Open();

To use Microsoft Access database make connection-string like this:-

Add following Namespace:-

using System.Data.OleDb;

Now on page_load or on button click event use this:-

OleDbConnection con = new OleDbConnection();
con = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=path of your .mdb file");
con.open();

Enjoy:)