js键盘数值

document.addEventListener('keydown', function(event) {
    // 获取键码
    console.log('Key Code:', event.keyCode);

    // 获取键值
    console.log('Key Value:', event.key);

    // 判断是否为数字键
    if (event.key >= '0' && event.key <= '9') {
        console.log('You pressed a number key:', event.key);
    }
});

document.addEventListener('keydown', function(event) {
    if (event.key >= 'A' && event.key <= 'Z') {
        if (event.getModifierState('Shift')) {
            console.log('Uppercase:', event.key);
        } else {
            console.log('Lowercase:', event.key);
        }
    }
});

let keyTimer;
document.addEventListener('keydown', function(event) {
    clearTimeout(keyTimer);
    keyTimer = setTimeout(() => {
        console.log('Key pressed:', event.key);
    }, 50); // 50ms 内重复按键视为一次按键
});

document.addEventListener('keyup', function(event) {
    clearTimeout(keyTimer);
});