// snippet shows how interfaces and coclasses can adorn the guid attribute. // running the regasm will generate .reg and .tlb files. reg file can be // used to register the interface and coclass with the registry. tlb file // are used to do interop. also illustrates how system.guid can be constructed // and how guid objects can be compared.
namespace guidsnippet { //<snippet1> using system; using system.runtime.interopservices;
// guid for the interface ifoo. [guid("f9168c5e-ceb2-4faa-b6bf-329bf39fa1e4")] interface ifoo { void foo(); }
// guid for the coclass cfoo. [guid("936da01f-9abd-4d9d-80c7-02af85c822a8")] public class cfoo : ifoo { // run regasm on this assembly to create .reg and .tlb files. // reg file can be used to register this coclass in the registry. // tlb file will be used to do interop.
public void foo() {}
public static void main( string []args ) { // snippet addresses the following in system.runtime.interopservices.guidattribute. // how to specify the attribute on interface/coclass. // retrieve the guidattribute from an interface/coclass. // value property on guidattribute class.
// snippet addresses the following in system.guid. // constructor guid(string). // constructor guid(bytearray). // equals. // operator ==. // compareto.
// the value property of guidattribute returns a string. system.console.writeline( "ifoo attribute: " + ((guidattribute)ifooattribute).value );
// using the string to create a guid. guid guidfoo1 = new guid( ((guidattribute)ifooattribute).value ); // using a byte array to create a guid. guid guidfoo2 = new guid ( guidfoo1.tobytearray() );
// equals is overriden and so value comparison is done though references are different. if ( guidfoo1.equals( guidfoo2 ) ) system.console.writeline( "guidfoo1 equals guidfoo2" ); else system.console.writeline( "guidfoo1 not equals guidfoo2" );
// equality operator can also be used to determine if two guids have same value. if ( guidfoo1 == guidfoo2 ) system.console.writeline( "guidfoo1 == guidfoo2" ); else system.console.writeline( "guidfoo1 != guidfoo2" );
// compareto returns 0 if the guids have same value. if ( guidfoo1.compareto( guidfoo2 ) == 0 ) system.console.writeline( "guidfoo1 compares to guidfoo2" ); else system.console.writeline( "guidfoo1 does not compare to guidfoo2" );
