Returning good old string parameters with Type.InvokeMemb er

[Marek]

Hi
I need to be able to return a string from a VB6 method:

Public Sub GetMessageAsPar ameter(ByRef message As String)
message = "GetMessageAsPa rameter worked!"
End Sub

which is implemented inside an ActiveX DLL. I need to do this using late
binding so I am trying to do it with code like this:

object[] parameters = new object[1];
ParameterModifi er parameterModifi ers = new ParameterModifi er(1);

// Allocate some space for the parameter
parameters[0] = new string(' ', 100);

parameterModifi ers[0] = true;
ParameterModifi er[] parameterModifi er = { parameterModifi ers };

comType.InvokeM ember("GetMessa geAsParameter",
BindingFlags.In vokeMethod, null, comObject, parameters, parameterModifi er,
null, null);

Console.WriteLi ne(String.Forma t("\nGetMessage AsParameter:
Message={0}", parameters[0].ToString()));

The problem is that I never get anything coming back. I don't get any
TargetInvocatio nExceptions either. I've tried all the different options of
ByVal and ByRef without success.

Please could anyone advise.

Thanks

Marek

[Marek]

Hi
I've worked it out:

parameters[0] = new StringBuilder(1 00).ToString();

Thanks.

Marek

"Marek" wrote:

Hi
I need to be able to return a string from a VB6 method:

Public Sub GetMessageAsPar ameter(ByRef message As String)
message = "GetMessageAsPa rameter worked!"
End Sub

which is implemented inside an ActiveX DLL. I need to do this using late
binding so I am trying to do it with code like this:

object[] parameters = new object[1];
ParameterModifi er parameterModifi ers = new ParameterModifi er(1);

// Allocate some space for the parameter
parameters[0] = new string(' ', 100);

parameterModifi ers[0] = true;
ParameterModifi er[] parameterModifi er = { parameterModifi ers };

comType.InvokeM ember("GetMessa geAsParameter",
BindingFlags.In vokeMethod, null, comObject, parameters, parameterModifi er,
null, null);

Console.WriteLi ne(String.Forma t("\nGetMessage AsParameter:
Message={0}", parameters[0].ToString()));

The problem is that I never get anything coming back. I don't get any
TargetInvocatio nExceptions either. I've tried all the different options of
ByVal and ByRef without success.

Please could anyone advise.

Thanks

Marek

[Marek]

Not sure what happened with the previous reply (appears blank), but the fix
for my problem was:

parameters[0] = new StringBuilder(1 00).ToString();

"Marek" wrote:

Hi
I need to be able to return a string from a VB6 method:

Public Sub GetMessageAsPar ameter(ByRef message As String)
message = "GetMessageAsPa rameter worked!"
End Sub

which is implemented inside an ActiveX DLL. I need to do this using late
binding so I am trying to do it with code like this:

object[] parameters = new object[1];
ParameterModifi er parameterModifi ers = new ParameterModifi er(1);

// Allocate some space for the parameter
parameters[0] = new string(' ', 100);

parameterModifi ers[0] = true;
ParameterModifi er[] parameterModifi er = { parameterModifi ers };

comType.InvokeM ember("GetMessa geAsParameter",
BindingFlags.In vokeMethod, null, comObject, parameters, parameterModifi er,
null, null);

Console.WriteLi ne(String.Forma t("\nGetMessage AsParameter:
Message={0}", parameters[0].ToString()));

The problem is that I never get anything coming back. I don't get any
TargetInvocatio nExceptions either. I've tried all the different options of
ByVal and ByRef without success.

Please could anyone advise.

Thanks

Marek