从C ++ dll返回字符串到VB [英] return a string from c++ dll to VB

问题描述

亲爱的所有

如何从c ++ dll返回字符串到VB?

我想通过返回值而不是参数返回字符串.

谷歌搜索了很多次....但是我找不到解决方法.

这是我的示例代码，但是当调用function(testBSTR())时，

示例程序崩溃了.

怎么了?那可能吗?

 

= c ++ dll代码=

外部"C" __declspec(dllexport)BSTR __stdcall testBSTR(){
BSTR消息；
LPSTR szData ="abcd";

消息= SysAllocStringByteLen(szData，strlen(szData));

返回消息；
}

= VB代码=

私有声明函数testBSTR Lib"MFCDLLTest.dll"； ()作为字符串

--------------------------------------------------- ------------

 

将lpRet设置为字符串

lpRet = testBSTR()<-已崩溃！

MsgBox(lpRet)

 

解决方案

在以下网址查看文章

http://support.microsoft.com/kb/187912/zh-CN

再见.

Dear, all

How can I return a string from c++ dll to VB?

I want to return a string through return value, not param.

So many times, googling.... but i couldn't find the solution.

Here is my sample code, but when the function(testBSTR()) is called,

the sample program is crashed.

What is wrong? Is that possible way?

 

= c++ dll code =

extern "C" __declspec(dllexport) BSTR __stdcall testBSTR() {
BSTR Message;
LPSTR szData = "abcd";

Message = SysAllocStringByteLen (szData, strlen(szData));

return Message;
}

= VB code =

Private Declare Function testBSTR Lib "MFCDLLTest.dll" () As String

-----------------------------------------------------------

 

Dim lpRet As String

lpRet = testBSTR () <- is crashed!!

MsgBox(lpRet )

 

解决方案

Take a look at the article at the following web address

http://support.microsoft.com/kb/187912/en-us

Bye.

这篇关于从C ++ dll返回字符串到VB的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！