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 |