准备工作：安装 VS2017 和win10 sdk （安装VS2017的时候要勾选上）
1.windows.h 中关于int类型的自定义（具体是在windef.h 的minwindef.h中）
Data type Size Signed? BYTE 8 bits Unsigned DWORD 32 bits Unsigned INT32 32 bits Signed INT64 64 bits Signed LONG 32 bits Signed LONGLONG 64 bits Signed UINT32 32 bits Unsigned UINT64 64 bits Unsigned ULONG 32 bits Unsigned ULONGLONG 64 bits Unsigned WORD 16 bits Unsigned 还有BOOL 类型 的宏定义（其实本质上也是int类型）typedef int BOOL;
也就是说BOOL可以接收任何 int类型的变量，可以用0和非0来判断一个函数是否执行成功
#define FALSE 0
#define TRUE 1
（区别于C++中的 bool： true false 均小写 ：只能接收 true 和false）
2.windows.h 中关于指针类型的自定义
For example, LPRECT is a pointer to a RECT, where RECT is a structure that describes a rectangle.
下面三种是等价的：
RECT* rect; // Pointer to a RECT structure. LPRECT rect; // The same PRECT rect; // Also the same. 注：LP称为长指针，又称为远指针 作用是访问当前segment外的内存，不过当初设计是为了 将16bit软件迁移到32bit windows上 现在没用了，三者一样
指针的精度 （本身的类型为 数值类型 只是为相应的指针提供精度 详见下面的源代码）
DWORD_PTRINT_PTRLONG_PTRULONG_PTRUINT_PTR 取决于编译器的位数 如果在32bit 上 就是32bit 在64bit编译器上编译就是64bit
下面是源代码（64bit）
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#if defined(_WIN64) typedef __int64 INT_PTR, *PINT_PTR; typedef unsigned __int64 UINT_PTR, *PUINT_PTR; typedef __int64 LONG_PTR, *PLONG_PTR; typedef unsigned __int64 ULONG_PTR, *PULONG_PTR; #define __int3264 __int64
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typedef ULONG_PTR DWORD_PTR, *PDWORD_PTR;
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3.重中之重 ————windows unicode 编码
Windows represents Unicode characters using UTF-16 encoding, in which each character is encoded as a 16-bit value. UTF-16 characters are called wide characters, to distinguish（区别于) them from 8-bit ANSI characters. The Visual C++ compiler supports the built-in data type （ Visual C++编译器内置数据类型）wchar_t for wide characters.
The header file WinNT.h also defines the following typedef.
typedef wchar_t WCHAR;
定义一个宽字符类型的字符需要 在字符或者字符串 需要在前面加上一个L
wchar_t a = L'a'; wchar_t *str = L"hello";wchar_t a = L'a';wchar_t *str = L"hello";
Here are some other string-related typedefs that you will see:
Typedef Definition CHAR char PSTR or LPSTR char* PCSTR or LPCSTR const char* PWSTR or LPWSTR wchar_t* PCWSTR or LPCWSTR const wchar_t*window 提供的api 也是 分为 ANSI 版本 即 ascii码版本和 unicode 版本 （底层 Windows会将 ascii 转换为unicode编码 一些新的windows 的api 只有unicode版本 所以最好用unicode版本的api ）
对于定义了 UNICODE 宏的程序 自动调用 UNICODE版本
下面是 SetWindowText的宏定义example
#ifdef UNICODE #define SetWindowText SetWindowTextW #else #define SetWindowText SetWindowTextA #endifTEXT函数的问题——编译时选择版本问题 尽量不要用了 过时了 详见下面的文档
Back when applications needed to support both Windows NT as well as Windows 95, Windows 98, and Windows Me, it was useful to compile the same code for either ANSI or Unicode strings, depending on the target platform. To this end, the Windows SDK provides macros that map strings to Unicode or ANSI, depending on the platform.
Macro Unicode ANSI TCHAR wchar_t char TEXT("x") L"x" "x"
For example, the following code:
SetWindowText(TEXT("My Application"));resolves to one of the following:
SetWindowTextW(L"My Application"); // Unicode function with wide-character string. SetWindowTextA("My Application"); // ANSI function.The TEXT and TCHAR macros are less useful today, because all applications should use Unicode. However, you might see them in older code and in some of the MSDN code examples.
_UNICODE 宏定义问题
有一些c运行时头文件库需要这个宏定义 以便正确调用unicode版本的函数
The headers for the Microsoft C run-time libraries define a similar set of macros. For example, _tcslen resolves to strlen if _UNICODE is undefined; otherwise it resolves to wcslen, which is the wide-character version of strlen.
#ifdef _UNICODE #define _tcslen wcslen #else #define _tcslen strlen #endifBe careful: Some headers use the preprocessor symbol UNICODE, others use _UNICODE with an underscore prefix. Always define both symbols.Visual C++ sets them both by default when you create a new project.
