how to use char* in .NET with DllImport

[Guest pai]

I write a DLL file in eVc++

extern "C" _declspec(dllexport) char* text2()

{

	char text[20];

	strcpy(text, "hello world");

	return text;

}

And I want to use this DLL in my .NET c#

 [DllImport("cal.dll")]

  static extern  string text2();

But I got Exception for

System.NotSupportedException:NotSupportedException

Does anyone here know this problem?

Thanks

[Guest filao]

Try using the StringBuilder class instead of a char array ...

A quick Google brought this up:

http://msdn.microsoft.com/library/default....gforstrings.asp

Hope this helps

[Guest pai]

after a few days, I get a result:

use function like "int func(TCHAR* arg);" in C++ DLL.

And in C# using Int32 func(StringBuilder arg); to use this function.

Thanks filao

Edited May 2, 2005 by pai