Attributes to interoperate with COM components in C#
Attributes in C# are used to provide information at design time and as well as at run-time. There are different types of attributes available in C# to interoperate with COM components.
COMImport attribute: COMImport attribute marks the class as an externally implemented COM class and a class declaration enables the use of a C# name to refer to a COM class.
[AttributeUsage(AttributeTargets.Class)]
public class COMImportAttribute : System.Attribute
{
public COMImportAttribute() { }
}
COMVisibility attribute: This attribute is used to specify whether or not a class or interface is visible in COM.
public class COMVisibilityAttribute: System.Attribute
{
public COMVisibilityAttribute(System.Interop.ComVisibility value) {}
public ComVisibilityAttribute Value { get {} }
}
There are many other attributes. Those are
-
The DispId attribute
-
The DllImport attribute
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The GlobalObject attribute
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The Guid attribute
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The HasDefaultInterface attribute
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The ImportedFromCOM attribute
-
The In and Out attributes
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The InterfaceType attribute
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The IsCOMRegisterFunction attribute
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The Marshal attribute
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The Name attribute
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The NoIDispatch attribute
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The NonSerialized attribute
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The Predeclared attribute
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The ReturnsHResult attribute
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The Serializable attribute
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The StructLayout attribute
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The StructOffset attribute
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The TypeLibFunc attribute
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The TypeLibType attribute
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The TypeLibVar attribute
All these above attributes are used to interoperate with COM components from C#.
