This doesn’t mean we don’t use a connection what it does mean is that we don’t hold the connection. Opening the ConnectionĪDO.NET uses a disconnected model. An example of reading the connection string and initializing the connection object is shown in listing 2. NET.Īfter we have defined the connection string and externalized it in the App.config file we can read the ConnectionString key’s value using the ConfigurationSettings class. And, copy the ConnectionString from the Properties window (see figure 3)įigure 3: Copy the connection string for a specific database from the Properties window in Visual Studio.Select the database in the Server Explorer.Make sure the computer with the database is registered in the Server Explorer.To copy the connection string from the Properties window: udl text files and is a good way to build a connection string for OleDb providers. NET.įigure 2: The Data Link Properties editor can be used to edit. udl files or simply copy and paste the connection string from the Properties window in Visual Studio. Your connection string will vary, but an excellent way to build a connection string is to use the Data Links Properties (see figure 2) dialog used to edit. In the example the key is named ConnectionString and the value is an actual connection string for an MS SQL Server instance of the Northwind database. The key is the name we use to access the value with, and the value defines the value we want externalize. elements are added as key and value pairs. It is shown wrapped due to margin limits set in my word processor. Ĭaution: The value parameter is a contiquous string on a single line in the. Listing 1: Defining the connection string in the element in a. Listing 1 contains the App.config file for our example program, including an initialized connection string.įigure 1: The Application Configuration File template will add an App.config file to your project. We can add an App.config file to our project manually or by selecting File|Add New Item and picking the Application Configuration applet from the Add New Item dialog (see figure 1).
#Visual basic .net windows#
Our demo application is a Windows application. NET already provides with a means of reading this information. If we place the connection string information in an tag in the. If you are writing a Web application then you can place the connection string in the Web.config file that is created with Web applications.Ĭonveniently we can use the class’ shared collection AppSettings to read from an application configuration file. If you are writing a Windows application then you can add an Application Configuration file to your project. Externalizing the Connection StringĪ technique I prefer to use is to externalize the connection string information in a. For our demonstration we will be using MS SQL Server 2000, so will use the SqlClient ADO.NET classes. For everything else you will need to use the classes in namespace. If you are connecting to MS SQL Server 7.0 or greater then you will need to use the classes in namespace. In order to connect to a database you need to know which category the database falls into. You will need a database to connect to, a connection string, and Visual Basic. To do so you will need a couple of bits of information.
#Visual basic .net how to#
The examples in this section demonstrate how to connection to a typical database. Connecting to a DatabaseĪDO.NET supports using both traditional databases as data providers and non-traditional repositories for data. The techniques demonstrated work with most of the databases you are likely to encounter, including MS SQL Server, DB2 Universal Database, MS Access, Oracle, Informix, and any other database that works with ODBC. The information contained herein will provide you with the most common skills you will need to professionally incorporate stored procedures into your applications. And, use both Input and Output parameters with stored procedures.Create an adapter and fill a DataSet with data returned from a stored procedure.Externalize connection string information in an XML configuration file.In this article I will demonstrate how to: In this part I will demonstrate how you can codify the analogous steps to incorporate stored procedures into your Visual Basic. Part 1 of “Programming with Stored Procedures” demonstrated how you can edit and test stored procedures without leaving Visual Studio.
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