钩子初接触（二十九）
结构7：KBDLLHOOKSTRUCT Structure
The KBDLLHOOKSTRUCT structure contains information about a low-level keyboard input event.
该结构包含有低层键盘输入事件的信息。
Syntax语法
typedef struct {
DWORD vkCode;
DWORD scanCode;
DWORD flags;
DWORD time;
ULONG_PTR dwExtraInfo;
} KBDLLHOOKSTRUCT, *PKBDLLHOOKSTRUCT;
Members成员
vkCode
Specifies a virtual-key code. The code must be a value in the range 1 to 254. 指定虚拟键值。该值必须在1到254的范围内。
scanCode
Specifies a hardware scan code for the key.指定键的硬件扫描码。
flags
Specifies the extended-key flag, event-injected flag, context code, and transition-state flag. This member is specified as follows. An application can use the following values to test the keystroke flags.
指定扩展键标志，事件注入标志，上下文代码，转换状态码。成员如下所示。应用程序可以使用下列值来检查键盘敲击标志。
| Value值 |
Purpose目的 |
| LLKHF_EXTENDED |
Test the extended-key flag. 测试扩展键标志。 |
| LLKHF_INJECTED |
Test the event-injected flag. 测试事件注入标志。 |
| LLKHF_ALTDOWN |
Test the context code. 测试上下文代码。 |
| LLKHF_UP |
Test the transition-state flag. 测试转换状态码。 |
0 ：Specifies whether the key is an extended key, such as a function key or a key on the numeric keypad. The value is 1 if the key is an extended key; otherwise, it is 0. 指定该键是否是扩展键，例如：功能键、数字键盘上的键。是扩展键为1，否则为0。
1-3 ：Reserved. 保留。
4 ：Specifies whether the event was injected. The value is 1 if the event was injected; otherwise, it is 0. 指定事件是否被注入。被注入为1，否则为0。
5 ：Specifies the context code. The value is 1 if the ALT key is pressed; otherwise, it is 0. 指定上下文代码。如果按下了ALT，该值为1，否则为0
6 ：Reserved. 保留。
7 ：Specifies the transition state. The value is 0 if the key is pressed and 1 if it is being released.指定转换状态。如果该键被按下该值为1，如果被释放为0。
time
Specifies the time stamp for this message, equivalent to what GetMessageTime would return for this message. 指定消息的时间戳，相当于GetMessageTime返回的值。
dwExtraInfo
Specifies extra information associated with the message. 指定和该消息相关联的扩展信息。
Helios 2007-5-31