>>>

>>>[DllImport("ww_local.dll")]
>>>static extern string Invoke1(string cInvokeString);
>>>

>>
>>Should this dll still be in the References of the project?
>>
>>Also, once declared this way, how should I call it?
>
>No, it doesn't need to be in References.
>
>Once it's declared it's basically just a static method call.
>
>

>string result = Invoke1("StringHere");
>

Just to be very clear, the DllImport/static must be in an existing class definition. Ex.

public static SampleClass
{
    [DllImport("ww_local.dll")]
    static extern string Invoke1(string cInvokeString);
}

Then you'd call it from your code:

public void DoSomething()
{
    string result = SampleClass.Invoke1("String");
}