为啥我无法使用 DirectInput 获取键盘？
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【中文标题】为啥我无法使用 DirectInput 获取键盘？【英文标题】：Why can I not acquire the keyboard with DirectInput?为什么我无法使用 DirectInput 获取键盘？ 【发布时间】：2013-03-27 21:07:45 【问题描述】：我今天刚开始接触 DirectInput，在 Windows 7 Ultimate N 上使用 DirectInput8 和 MinGW。我从一个简单的程序开始，每秒报告哪些键当前处于关闭状态（只是代码，不可读的键）。但是，我什至无法在键盘出错之前获得它：
#define _WIN32_WINNT 0x0601
#include <dinput.h>
//link to dinput8.lib and dxguid.lib
int main()
IDirectInput8 *dinput;
DirectInput8Create(GetModuleHandle(nullptr), DIRECTINPUT_VERSION, IID_IDirectInput8, (void **)&dinput, nullptr);
IDirectInputDevice8 *kb;
dinput->CreateDevice(GUID_SysKeyboard, &kb, nullptr);
kb->SetDataFormat(&c_dfDIKeyboard);
kb->SetCooperativeLevel(GetConsoleWindow(), DISCL_FOREGROUND | DISCL_NONEXCLUSIVE);
kb->Acquire(); //fails with DIERR_INVALIDPARAM
我省略了错误检查，但结果是每次调用都成功（根据FAILED 宏的判断）直到Acquire()。该调用失败并出现错误DIERR_INVALIDPARAM。我查看了 MSDN 页面和整个网络，但根据它存在和工作之前的所有内容，我找不到任何失败的原因。
为了更好地衡量，我还尝试循环调用 Acquire() 直到它成功，然后在它运行时玩弄 Windows 和键盘，但程序在它运行的所有时间都没有成功获取键盘。如何成功获取键盘？
【问题讨论】：
仅供参考，Microsoft 不鼓励使用 DirectInput。它基本上是一个围绕 Win32 原始输入的过度设计的包装器，其主要作用是产生一些不必要的线程，并引入一些开销。如果您想在此级别处理键盘或鼠标输入，只需使用原始输入 API @jalf，我计划最终检测 Motioninjoy PS3 控制器输入用于我自己的目的 :) 键盘是许多教程的第一部分，所以我决定至少在开始之前让它工作 -出来。 【参考方案1】：在控制台程序中尝试直接输入键盘和操纵杆
使用直接输入不需要窗口句柄。您可以在参数中使用 null 作为窗口句柄。
代替：
kb->SetCooperativeLevel(GetConsoleWindow(), DISCL_FOREGROUND | DISCL_NONEXCLUSIVE);
用途：
kb->SetCooperativeLevel(NULL, DISCL_FOREGROUND | DISCL_NONEXCLUSIVE);
这是一个示例程序，它使用直接输入来在按下这些键时显示键“a”和“d”。当这些键被按住 300 毫秒时，它将重复这些键。该示例程序也是高分辨率计数器的一个很好的示例。无需在 Visual Studio 中添加属性即可添加库 dinput8.lib 和 dxguid.lib。程序顶部的#pragma 注释代码行会为您执行此操作。
#include <dinput.h>
#include <iostream>
#include <Windows.h>
#pragma comment(lib,"dinput8.lib")
#pragma comment(lib,"dxguid.lib")
using std::cout;
using std::endl;
LPDIRECTINPUT8 di;
LPDIRECTINPUTDEVICE8 keyboard;
class CTimer
public:
CTimer()
QueryPerformanceFrequency(&mqFreq);
~CTimer()
void Start()
QueryPerformanceCounter(&mqStart);
void End()
QueryPerformanceCounter(&mqEnd);
double GetTimeInSeconds()
return (mqEnd.QuadPart - mqStart.QuadPart)/(double)mqFreq.QuadPart;
double GetTimeInMilliseconds()
return (1.0e3*(mqEnd.QuadPart - mqStart.QuadPart))/mqFreq.QuadPart;
double GetTimeInMicroseconds()
return (1.0e6*(mqEnd.QuadPart - mqStart.QuadPart))/mqFreq.QuadPart;
double GetTimeInNanoseconds()
return (1.0e9*(mqEnd.QuadPart - mqStart.QuadPart))/mqFreq.QuadPart;
private:
LARGE_INTEGER mqStart;
LARGE_INTEGER mqEnd;
LARGE_INTEGER mqFreq;
;
HRESULT initializedirectinput8()
HRESULT hr;
// Create a DirectInput device
if (FAILED(hr = DirectInput8Create(GetModuleHandle(NULL), DIRECTINPUT_VERSION,
IID_IDirectInput8, (VOID**)&di, NULL)))
return hr;
void createdikeyboard()
di->CreateDevice(GUID_SysKeyboard, &keyboard, NULL);
keyboard->SetDataFormat(&c_dfDIKeyboard);
keyboard->SetCooperativeLevel(NULL,DISCL_FOREGROUND | DISCL_EXCLUSIVE);
keyboard->Acquire();
void destroydikeyboard()
keyboard->Unacquire();
keyboard->Release();
#define keydown(name,key) (name[key] & 0x80)
void main()
HRESULT hr;
BYTE dikeys[256];
CTimer timeint;
CTimer timekeywaspressedclass;
double gettime;
double lastkeywasa=false;
double timekeywaspressed=0;
bool lasttimetherewasakeypress=false;
bool akeywaspressed=false;
initializedirectinput8();
createdikeyboard();
hr=keyboard->GetDeviceState(256,dikeys);
timeint.Start();
while (!keydown(dikeys,DIK_ESCAPE))
timeint.End();
gettime=timeint.GetTimeInMilliseconds();
if (gettime >=5)
hr=keyboard->GetDeviceState(256,dikeys);
akeywaspressed=false;
if (keydown(dikeys,DIK_A))
akeywaspressed=true;
if (timekeywaspressed >=300)
cout << "a";
lasttimetherewasakeypress=false;
if (keydown(dikeys,DIK_D))
akeywaspressed=true;
if (timekeywaspressed >=300)
cout << "d";
lasttimetherewasakeypress=false;
if (lasttimetherewasakeypress==false && akeywaspressed==true)
timekeywaspressedclass.Start();
timekeywaspressed=0;
lasttimetherewasakeypress=true;
if (lasttimetherewasakeypress==true && akeywaspressed==true)
timekeywaspressedclass.End();
gettime=timekeywaspressedclass.GetTimeInMilliseconds();
timekeywaspressed+=gettime;
timekeywaspressedclass.Start();
if (akeywaspressed==false)
lasttimetherewasakeypress=false;
timekeywaspressed=0;
// end if (gettime >=5)
// end while
destroydikeyboard();
// end main
这是一个操纵杆的示例控制台程序。
#include <dinput.h>
#include <iostream>
#include <Windows.h>
#pragma comment(lib,"dinput8.lib")
#pragma comment(lib,"dxguid.lib")
using std::cout;
using std::endl;
LPDIRECTINPUT8 di;
LPDIRECTINPUTDEVICE8 joystick;
LPDIRECTINPUTDEVICE8 keyboard;
DIJOYSTATE2 js;
BOOL CALLBACK enumCallback(const DIDEVICEINSTANCE* instance, VOID* context);
BOOL CALLBACK enumAxesCallback(const DIDEVICEOBJECTINSTANCE* instance, VOID* context);
HRESULT selectjoystick()
HRESULT hr;
// Look for the first simple joystick we can find.
if (FAILED(hr = di->EnumDevices(DI8DEVCLASS_GAMECTRL, enumCallback,
NULL, DIEDFL_ATTACHEDONLY)))
return hr;
// Make sure we got a joystick
if (joystick == NULL)
// printf("Joystick not found.\n");
return E_FAIL;
DIDEVCAPS capabilities;
HRESULT setjoystickproperties()
HRESULT hr;
// Set the data format to "simple joystick" - a predefined data format
//
// A data format specifies which controls on a device we are interested in,
// and how they should be reported. This tells DInput that we will be
// passing a DIJOYSTATE2 structure to IDirectInputDevice::GetDeviceState().
if (FAILED(hr = joystick->SetDataFormat(&c_dfDIJoystick2)))
return hr;
// Set the cooperative level to let DInput know how this device should
// interact with the system and with other DInput applications.
if (FAILED(hr = joystick->SetCooperativeLevel(NULL, DISCL_EXCLUSIVE |
DISCL_FOREGROUND)))
return hr;
// Determine how many axis the joystick has (so we don't error out setting
// properties for unavailable axis)
capabilities.dwSize = sizeof(DIDEVCAPS);
if (FAILED(hr = joystick->GetCapabilities(&capabilities)))
return hr;
BOOL CALLBACK enumCallback(const DIDEVICEINSTANCE* instance, VOID* context)
HRESULT hr;
// Obtain an interface to the enumerated joystick.
hr = di->CreateDevice(instance->guidInstance, &joystick, NULL);
// If it failed, then we can't use this joystick. (Maybe the user unplugged
// it while we were in the middle of enumerating it.)
if (FAILED(hr))
return DIENUM_CONTINUE;
// Stop enumeration. Note: we're just taking the first joystick we get. You
// could store all the enumerated joysticks and let the user pick.
return DIENUM_STOP;
HRESULT enumaxes()
HRESULT hr;
// Enumerate the axes of the joyctick and set the range of each axis. Note:
// we could just use the defaults, but we're just trying to show an example
// of enumerating device objects (axes, buttons, etc.).
if (FAILED(hr = joystick->EnumObjects(enumAxesCallback, NULL, DIDFT_AXIS)))
return hr;
BOOL CALLBACK enumAxesCallback(const DIDEVICEOBJECTINSTANCE* instance, VOID* context)
HWND hDlg = (HWND)context;
DIPROPRANGE propRange;
propRange.diph.dwSize = sizeof(DIPROPRANGE);
propRange.diph.dwHeaderSize = sizeof(DIPROPHEADER);
propRange.diph.dwHow = DIPH_BYID;
propRange.diph.dwObj = instance->dwType;
propRange.lMin = -1000;
propRange.lMax = +1000;
// Set the range for the axis
if (FAILED(joystick->SetProperty(DIPROP_RANGE, &propRange.diph)))
return DIENUM_STOP;
return DIENUM_CONTINUE;
HRESULT polljoy()
HRESULT hr;
if (joystick == NULL)
return S_OK;
// Poll the device to read the current state
hr = joystick->Poll();
if (FAILED(hr))
// DInput is telling us that the input stream has been
// interrupted. We aren't tracking any state between polls, so
// we don't have any special reset that needs to be done. We
// just re-acquire and try again.
hr = joystick->Acquire();
while (hr == DIERR_INPUTLOST)
hr = joystick->Acquire();
// If we encounter a fatal error, return failure.
if ((hr == DIERR_INVALIDPARAM) || (hr == DIERR_NOTINITIALIZED))
return E_FAIL;
// If another application has control of this device, return successfully.
// We'll just have to wait our turn to use the joystick.
if (hr == DIERR_OTHERAPPHASPRIO)
return S_OK;
// Get the input's device state
if (FAILED(hr = joystick->GetDeviceState(sizeof(DIJOYSTATE2), &js)))
return hr; // The device should have been acquired during the Poll()
return S_OK;
class CTimer
public:
CTimer()
QueryPerformanceFrequency(&mqFreq);
~CTimer()
void Start()
QueryPerformanceCounter(&mqStart);
void End()
QueryPerformanceCounter(&mqEnd);
double GetTimeInSeconds()
return (mqEnd.QuadPart - mqStart.QuadPart)/(double)mqFreq.QuadPart;
double GetTimeInMilliseconds()
return (1.0e3*(mqEnd.QuadPart - mqStart.QuadPart))/mqFreq.QuadPart;
double GetTimeInMicroseconds()
return (1.0e6*(mqEnd.QuadPart - mqStart.QuadPart))/mqFreq.QuadPart;
double GetTimeInNanoseconds()
return (1.0e9*(mqEnd.QuadPart - mqStart.QuadPart))/mqFreq.QuadPart;
private:
LARGE_INTEGER mqStart;
LARGE_INTEGER mqEnd;
LARGE_INTEGER mqFreq;
;
HRESULT initializedirectinput8()
HRESULT hr;
// Create a DirectInput device
if (FAILED(hr = DirectInput8Create(GetModuleHandle(NULL), DIRECTINPUT_VERSION,
IID_IDirectInput8, (VOID**)&di, NULL)))
return hr;
void createdikeyboard()
di->CreateDevice(GUID_SysKeyboard, &keyboard, NULL);
keyboard->SetDataFormat(&c_dfDIKeyboard);
keyboard->SetCooperativeLevel(NULL,DISCL_FOREGROUND | DISCL_EXCLUSIVE);
keyboard->Acquire();
void destroydikeyboard()
keyboard->Unacquire();
keyboard->Release();
void closejoystick()
if (joystick)
joystick->Unacquire();
if (joystick)
joystick->Release();
#define keydown(name,key) (name[key] & 0x80)
void main()
HRESULT hr;
CTimer pollintclass;
hr=initializedirectinput8();
createdikeyboard();
hr=selectjoystick();
hr=setjoystickproperties();
hr=enumaxes();
bool endloop=false;
double gettime;
BYTE dikeys[256];
pollintclass.Start();
while (endloop==false)
pollintclass.End();
gettime=pollintclass.GetTimeInMilliseconds();
if (gettime >=5)
hr=keyboard->GetDeviceState(256,dikeys);
if (FAILED(hr))
keyboard->Acquire();
if (keydown(dikeys,DIK_ESCAPE))
endloop=true;
polljoy();
cout << "joy x-axis=" << js.lX << " " << "joy y-axis=" << js.lY << endl;
pollintclass.Start();
destroydikeyboard();
closejoystick();
【讨论】：
【参考方案2】：您是否尝试过DISCL_BACKGROUND 而不是DISCL_FOREGROUND？
【讨论】：
【参考方案3】：实际上，当我将它从与控制台窗口（明显存在）关联更改为我在SetCooperativeLevel() 调用中创建的一个时，错误神奇地消失了。为什么不能使用控制台窗口我不知道，所以我会暂时不接受这个问题，而不是让回答者这样做，但这确实解决了问题。
【讨论】：
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