Visual Basic

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Private Declare Function method Lib "C:\Documents and Settings\CSfiles\interop\interop\bin\Debug\interop.dll" Alias "interopdll" (ByVal X As Integer, ByVal X As Integer)<br />
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Private Sub Command1_Click()<br />
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Dim a As Integer<br />
Dim obj As Object<br />
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obj = New sample ' I get a compile-time error for undefined user type here.<br />
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a = obj.method(CInt(Text1.Text), CInt(Text2.Text))<br />
Label1.Caption = CStr(a)<br />
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End Sub<br />
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using System;<br />
using System.Runtime.InteropServices;<br />
using System.Reflection;<br />
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[assembly: ComVisible(true)]<br />
namespace interop<br />
{<br />
/// <summary><br />
/// Summary description for Class1.<br />
/// </summary><br />
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[ClassInterface(ClassInterfaceType.AutoDual)]<br />
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[GuidAttribute("6CE9C732-CD90-4042-A5F0-CF71DFAC2598")]<br />
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class sample<br />
{<br />
public sample()<br />
{<br />
}<br />
public int c;<br />
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public void method(int a, int b)<br />
{ <br />
c = a+b;<br />
//return c;<br />
} <br />
}<br />
}<br />
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