Error C2664 : cannot convert parameter 1 from 'CString' to 'LPWSTR'

Question

0.00/5 (No votes)

See more:

I design one Win32 Dll application, in which one function returns handle and parameter is String so I used LPSTR in Dll application 'c' file,it builds successfully but when I using that function is MFC dialogue based application and I passed CString argument to that function,but it gives error as

VB

Error  C2664: ': cannot convert parameter 1 from 'CString' to 'LPWSTR'

so what are the arguments pass to that function?

Posted 18-Mar-13 2:46am

Venkat Raghvan

Updated 18-Mar-13 3:06am

v2

Add a Solution

Comments

[no name] 18-Mar-13 9:14am

Well if I were you, I would be passing a LPWSTR as a parameter. Did you try casting your CString to the correct type?

Tadit Dash (ତଡିତ୍ କୁମାର ଦାଶ) 18-Mar-13 9:43am

[Reply from OP]

No! how to cast that?

Richard MacCutchan 18-Mar-13 9:50am

Have you set the project's character set to UNICODE?

Jochen Arndt 18-Mar-13 9:59am

You should show us the relevant code parts. Passing CString objects to/from DLLs is problematic. If the string is constant (not changed by the function that receives it) and processed immediately (function did not use the string after the CString object goes out of scope), it may be sufficient to define the parameter as LPCTSTR.

A CString can not be casted to LPWSTR / LPSTR / LPTSTR. These types are not const (string can be changed). To access a CString to change the content, use CString::GetBuffer() and CString::ReleaseBuffer() when finished.

nv3 18-Mar-13 10:32am

Thank would get my 5 if you posted it as a solution.

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Eugen Podsypalnikov · Answer 1 · 2013-03-18T03:45:00

Solution 1

You can cast a CString object to a const pointer :)

C++

HANDLE Test(LPCTSTR szEntry)
{
  HANDLE hRet(NULL);

  // use szEntry here

  return hRet;
}

// CString CYourDlg::m_cszEntry
void CYourDlg::OnTest()
{
  UpdateData(TRUE);
  
  HANDLE hEntry(Test(m_cszEntry));
  
  // use hEntry here
}

Posted 18-Mar-13 3:45am

Eugen Podsypalnikov