SendInput() Keyboard letters C/C++

Question

I am trying to use SendInput() to send a sentence to another application (Notepad) and then send it hitting the Enter Key.

Any code snippets? Or help

Solution 1

INPUT input;
WORD vkey = VK_F12; // see link below
input.type = INPUT_KEYBOARD;
input.ki.wScan = MapVirtualKey(vkey, MAPVK_VK_TO_VSC);
input.ki.time = 0;
input.ki.dwExtraInfo = 0;
input.ki.wVk = vkey;
input.ki.dwFlags = 0; // there is no KEYEVENTF_KEYDOWN
SendInput(1, &input, sizeof(INPUT));

input.ki.dwFlags = KEYEVENTF_KEYUP;
SendInput(1, &input, sizeof(INPUT));

List of virtual key codes .....

Solution 2

I made a modification after reading @Nathan's code, this reference and combined with @jave.web's suggestion. This code can be used to input characters (both upper-case and lower-case).

#define WINVER 0x0500
#include<windows.h>
void pressKeyB(char mK)
{
    HKL kbl = GetKeyboardLayout(0);
    INPUT ip;
    ip.type = INPUT_KEYBOARD;
    ip.ki.time = 0;
    ip.ki.dwFlags = KEYEVENTF_UNICODE;
    if ((int)mK<65 || (int)mK>90) //for lowercase
    {
        ip.ki.wScan = 0;
        ip.ki.wVk = VkKeyScanEx( mK, kbl );
    }
    else //for uppercase
    {
        ip.ki.wScan = mK;
        ip.ki.wVk = 0;

    }
    ip.ki.dwExtraInfo = 0;
    SendInput(1, &ip, sizeof(INPUT));
}

Below is the function for pressing Return key:

    void pressEnter()
{
    INPUT ip;
    ip.type = INPUT_KEYBOARD;
    ip.ki.time = 0;
    ip.ki.dwFlags = KEYEVENTF_UNICODE;
    ip.ki.wScan = VK_RETURN; //VK_RETURN is the code of Return key
    ip.ki.wVk = 0;

    ip.ki.dwExtraInfo = 0;
    SendInput(1, &ip, sizeof(INPUT));

}

Solution 3

The SendInput function accepts an array of INPUT structures. The INPUT structures can either be a mouse or keyboard event. The keyboard event structure has a member called wVk which can be any key on the keyboard. The Winuser.h header file provides macro definitions (VK_*) for each key.

Comments

[jave.web]

Use VkKeyScanEx( char, KeyboardLayout ) to put your "common" chars into this example :) ... input.ki.wVk = VkKeyScanEx('a',kbl); as for the KeyboardLayout the simpliest way is to load current window's keyboardLayout: HKL kbl = GetKeyboardLayout(0);

[Lê Quang Duy]

Thank you and @jave.web for the answer. I made up my code for inputting character in the answer below (sorry I can't find how to insert code into comment section).

[Talset]

Just a note, in case others are confused: The pressEnter() function works for text fields/editors, but doesn't trigger a response in some form controls. The following post works correctly in both cases with VK_RETURN: stackoverflow.com/a/20857633/8690169

[Bobbie E. Ray]

Line 9 reads if ((int)mK<65 && (int)mK>90), i.e. the char code, cast to an int, must be smaller than 65 and larger than 90 at the same time. I assume this must be an or, i.e. if ((int)mK<65 || (int)mK>90), to match special and small chars in the ASCII table, otherwise the condition is mutually exclusive and can never be met

[Lê Quang Duy]

Thank you @BobbieE.Ray for pointing this out. I edited the post following your suggestion.

[Bobbie E. Ray]

Thanks for updating the code. If you could give my remark some kudos I'd appreciate it. I'm working my way so up that some day I can edit answers directly :) Thank you