delphi 中的 WideString 对应VB 什么函数或类型?

[seeQe]

有个DLL 中的函数原型:
extern "C" bool __declspec(dllexport) __stdcall EvideoOpenRoom(BSTR RoomIP, BSTR ServerIP, int iFlag)

用Delphi 调用时,能正确调用,具体如下:
声明:
function EvideoOpenRoom(RoomIP, ServerIP: WideString; iFlag: Integer): boolean;stdcall;
far;external 'SendWineEV.dll' name 'EvideoOpenRoom';

使用:
if EvideoOpenRoom(WideString(Edit2.Text), WideString(Edit1.Text), iFlag) then
begin
ShowMessage('发送指令成功');
end
end;

******************************************************************************************
如果使用VB 调用,无法正确执行
引用如下:
Public Declare Function EvideoOpenRoom Lib "SendWineEV.DLL" (ByVal strRoomIP As String, ByVal strServerIP As String, ByVal nFlag As Long) As Long

使用:
Private Sub btnOpenRoom_Click()
Dim nFlag As Long, nRet As Long
Dim strServerIP As String, strRoomIP As String

nFlag = 0
strRoomIP = Trim(Edit2.Text)
strServerIP = Trim(Edit1.Text)
nRet = EvideoOpenRoom(strRoomIP, strServerIP, nFlag)

End Sub

运行结果nRet = 0 也就是表示失败,产生动作效果也和dephi 中不同,不知道问题出在哪里,请高手指点,多谢多谢~~

[捧剑者]

试试：
Public Declare Function EvideoOpenRoom Lib "SendWineEV.DLL" (strRoomIP As Any, strServerIP As Any, ByVal nFlag As Long) As Long

Dim strServerIP() As byte, strRoomIP() As byte

[贝隆]

严格的说Delphi中的WideString在VB中无对应类型。

[捧剑者]

The WideString type represents a dynamically allocated string of 16-bit Unicode characters. In most respects it is similar to AnsiString. On Win32, WideString is compatible with the COM BSTR type.

[捧剑者]

所以，widestring 与vb6中的string相同，但是在vb6调用api时，会自动将unicode转化为ansi。用byte数组可以避免这样的转换。

[三断笛]

用strconv转化下?

[shaoyy]

BSTR 是windows中不同进程共享字符信息的标准类型，一位字符占两个字节，我VB不太熟悉，我觉你可以在VB中引入任意一个含有BSTR类型参数的COM控件（我的AC Report中就有这种参数的方法），看一下系统转换为什么类型。

[seeQe]

使用BSTR 是个智能字符串,定义成 long 就行了,谢谢各位

EvideoOpenRoom( RoomIP as long, ServerIP as long , iFlag as integer)