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Compiler Warning (level 1) C4397

Error Message

DefaultCharSetAttribute is ignored

DefaultCharSetAttribute is ignored by the Visual C++ compiler. To specify a character set for the DLL, use the CharSet option of DllImport. For more information, see Using C++ Interop (Implicit PInvoke).


The following sample generates C4397.

// C4397.cpp
// compile with: /W1 /c /clr
using namespace System;
using namespace System::Runtime::InteropServices;

[module:DefaultCharSetAttribute(CharSet::Unicode)];   // C4397

[DllImport("kernel32", EntryPoint="CloseHandle", CharSet=CharSet::Unicode)]   // OK
extern "C" bool ImportDefault(IntPtr hObject);

public ref class MySettingVC {
   void method() {

public ref struct StructDefault1{};

public ref class ClassDefault1{};