This is the basic implementation of 3 tier architecture in visual c# using windows form application with database.
Procedure:
Create a new windows for project and name it APP_LAYER Add a textbox and a button to the form1.cs Add a class library to the Project and name it B_LAYER Add another class library and name it D_LAYER Right click references in APP_LAYER, provide it reference of B_LAYER Right click references in B_LAYER, provide it the reference of D_LAYER This will link class libraries with eachother.
Create server based database:
Right Click on the project name in Solution Explorer -> ADD -> Click on Add NEW ITEM From the Dialog Box, Select Server Based Database and give it the desired name.
Create data tables in database:
From Server Explorer, Select the database name and right click on tables and choose add new table. Put in the desired fields and table name then Update the database to create table.
Create relevant functions in the class libraries as in the project and execute the code.