Type Converter and Its Implementation-1

Used
1. String-to-value conversion
2. Conversion during design and Runtime

Implementation:
For most basic data types (such as int32, bool, Char, string, and enumeration), the. NET Framework provides the default type converter.
The default type converter is inherited from the system. componentmodel. typeconverter class and is named typeconverternameconverter.
For example, if the attribute is set to height = "150px", but the attribute is in the unit type, the problem is to convert "150px" to the unit type.
The page compiler automatically calls system. Web. UI. webcontrols. unitconverter to complete the conversion.

However, the above method can only solve part 1 of the problem. You can customize the type converter at will.

Custom Type converters can be divided into three types:
Value translation type converter,
Type converter that provides standard value list to ide
Implement the initialization of generating Properties Based on ConstructorsCodeType Converter

Introduction:
1. Value Type Converter
Converts string to attribute type.

Using System;
Using System. Collections. Generic;
Using System. text;
Using System. componentmodel;
Using System. Globalization;
Using System. drawing;


Namespace Usercontrols
{
Public   Class Testconverter: typeconverter
{
Public   Override   Bool Canconvertfrom (itypedescriptorcontext context, type sourcetype)
{
If (Sourcetype =   Typeof (String ))
Return   True ;
Else
{
Return Base. Canconvertfrom (context, sourcetype );
}
}

Public   Override   Object Convertfrom (itypedescriptorcontext context, cultureinfo culture, Object Value)
{
If (Value Is   String )
{
String [] V = (( String ) Value). Split ( New   Char [] {','} );
Return   New Point ( Int . Parse (V [ 0 ]), Int . Parse (V [ 1 ]);

}
Return   Base . Convertfrom (context, culture, value );
}

Public   Override   Object Convertize (itypedescriptorcontext context, cultureinfo culture, Object Value, type destinationtype)
{
If (Destinationtype =   Typeof ( String ))
{
Return(Point) value). x+ "," +(Point) value). Y;
}
Return   Base . Convertize (context, culture, value, destinationtype );
}

}
}