Asp.net Class Library Tutorial
Collection of classes that provide standard functionality to execute common tasks (email services, database services, file system services, etc). The Class Library is organized by sections called Namespaces.
To include a Namespace in your application define as following:
<%@ Import Namespace=”System.Data” %>
System: Contains classes that define commonly used value and reference data types, events and event handlers, attributes and processing exceptions.
System.Web.UI.WebControls: Contains classes that allow creating web server controls on a Web page.
System.Web.UI.HTMLInput: Contains classes that allow creating HTML server controls on a Web page.
Microsoft.VisualBasic: Contains classes that support compilation and code generation using the Visual Basic language.
Function | Arguments | Return | Details |
IsNumeric() | Value to check | Boolean | Checks if the value is a number. If not it return False, if it a number it returns True |
IsDate() | Date to check | Boolean | Checks if the date is a valid format. If not it return False, if it a number it returns True |
Trim() | Value to trim | String | Removes blank spaces before and after the value |
Len() | Value to check | Integer | Count the number of characters inside the value |
CInt() | Value to convert | Integer | Converts a value into a Integer number |
CLng() | Value to convert | Long | Converts a value into a Long number |
Replace() | Value, original, replacement | String | Replaces string inside a value |
InStr() | Value, character | Integer | Find the position of the character in the value |
System.Data: Contains classes to build data sources for efficiently manage data.
Classes | Arguments | Methods | Details |
DataSet | -- | -- | In-memory cache of tables |
DataTable | TableName | Rows.Count | In-memory table |
DataColumn | Column Name |
| Structural definition of a DataTable column |
DataRow | Row Index |
| Represents a row of data in a DataTable |
System.Data.SqlClient: Contains classes to access data in SQL Server.
Classes | Arguments | Methods/Properties | Details |
SqlConnection | Server | Open() | Represents a connection to SQL Server database |
SqlCommand | Query | ExecuteNonQuery() | Update, insert, delete |
SqlDataReader | -- | Item(columname) | Gets a column value |
SqlDataAdapter | Query | Fill(DataTable) | Represents a select query that fills a DataSet/DataTable with the query results. |
System.Web.Mail: Contain a class to send emails and member functions and properties:
Class | Properties | Functions |
MailMessage | From |
