LPCWSTR Error - C++

Question

I'm trying to draw text to a window. Some enough, two things I'm wondering. Why can the tutorial I'm using not put an L"String Here" and I have to?

I'm confused about that, anyway back to the main point, I;m trying to draw text and I'm getting an error.

enter image description here

@LuchianGrigore, No, but the type of the parameter is. It would be a `LPCSTR` without. — chris, Jul 09 '13 at 20:50
@LuchianGrigore: `TextOut()` maps to either `TextOutA()` or `TextOutW()` depending on whether `UNICODE` is defined. In this case, it is defined, so `TextOutW()` is being called, and it expects `LPCWSTR` (ie `const wchar_t*`) as input, but a `const char*` from `std::string::c_str()` is being passed to it instead, hense the error. — Remy Lebeau, Jul 09 '13 at 20:51
@chris but then it wouldn't compile without UNICODE. He can use TCHAR* or TextOut (if it works, dunno) — Luchian Grigore, Jul 09 '13 at 20:52
try std::wstring s = "Hello, World!"; ... oops repeat response. — Seth Hays, Jul 09 '13 at 20:53
Fixed thanks guys. Why do I have to do that, and the book I'm learning from doesn't? Is it just the compiler? — Jordan Schnur, Jul 09 '13 at 20:53
@LuchianGrigore, I prefer it that way. `std::to_wstring` and everything still work, and supporting ANSI shouldn't be a requirement anymore. — chris, Jul 09 '13 at 20:54
@Jordan: the book is likely assuming that `UNICODE` is not being defined. — Remy Lebeau, Jul 09 '13 at 20:54
-1: Please don't post *images* of code and error messages -- post the actual code and the actual error message *as formatted text*. — John Dibling, Jul 09 '13 at 20:59

score 2 · Accepted Answer · answered Jul 09 '13 at 20:57

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If you have UNICODE defined in your project (which you should be default) then you can either use

wstring s = L"Hello, World!";

or the ANSI API for TextOut

TextOutA(hdc, 10, 10, s.c_str(), s.size());

answered Jul 09 '13 at 20:57

Neal

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score 1 · Answer 2 · edited May 23 '17 at 10:25

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See the following question:

What does LPCWSTR stand for and how should it be handled with?

Basically, you're trying to convert a regular character string to a wide character string implicitly and it won't allow you to do that. From the top answer:

To get a normal C literal string to assign to a LPCWSTR, you need to prefix it with L

LPCWSTR a = L"TestWindow";

edited May 23 '17 at 10:25

Community

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answered Jul 09 '13 at 21:01

gled

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LPCWSTR Error - C++

2 Answers2