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Unable to cast COM object of type 'System.__ComObject' to class type 'System.String

3
Hi,

Please help, this has been driving me nuts for nearly 2 days now.

This vb6 code works:

Public oEng As New ebizEngine
Public oMsg As ebizMessage

Function EbizGetFromQueue() As String
Set oMsg = oEng.RecvMessage
If oMsg Is Nothing Then
' the end
EbizGetFromQueue = "*END"
Else
EbizGetFromQueue = oMsg.Body
End If

In c# I have this:

private eBiz2000.ebizEngineClass ebizEngine = new eBiz2000.ebizEngineClass();

public string getFromQueue()
{
eBiz2000.ebizMessage ebizMessage;
ebizMessage = ebizEngine.RecvMessage();
if (ebizMessage == null) // not sure about this??
{
return "*END";
}

return (string)ebizMessage.Body;
}

When this runs I get the error Unable to cast COM object of type 'System.__ComObject' to class type 'System.String'. Instances of types that represent COM components cannot be cast to types that do not represent COM components; however they can be cast to interfaces as long as the underlying COM component supports QueryInterface calls for the IID of the interface.
I've tried numerous things with no success, any help is greatly appreciated.
Mar 26 '08 #1
2 6447
Plater
7,872 Expert 4TB
ebizMessage.Body is not a string type.
Mar 26 '08 #2
Bigi
3
ebizMessage.Body is not a string type.
It is an object, how can I get to the string it contains? How does the vb work but not the c#?
Mar 26 '08 #3

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