如何在 JavaScript 中触发键盘快捷键功能？

Question

我的网站中有记录功能。如果用户点击 Ctrl+Alt+R 将开始录制。现在我想在我的 html 页面中添加一个名为 RECORD 的按钮，以便用户点击该按钮时开始录制。

<button type="submit" class="btn btn-primary" data-toggle="tooltip" data-placement="top" onclick="record_session()" title="Start Recording">Record</button>

在我下面的函数中

function record_session(){
    //how can i trigger or initiate  ctrl+alt+r here??
}

Answer 1

如果你使用 jQuery，你可以添加按键事件：

$(document).keypress(function(e) {
    if (e.which === 114 && e.ctrlKey && e.altKey) {
        record_session();
    }
});

更新：

var enable_keypress = false;
function record_session(){
    enable_keypress = true;
}
$(document).keypress(function(e) {
    if (enable_keypress) {
        if (e.which === 114 && e.ctrlKey && e.altKey) { // ctrl+alt+r

        }
    }
});

更新 2

要触发键盘事件，你可以使用这个：

jQuery：

function keydown(ctrl, alt, shift, which, key) {
    var e = $.Event("keydown");
    e.ctrlKey = ctrl;
    e.altKey = alt;
    e.shiftKey = shift;
    if (typeof which === 'string') {
        key = which;
        which = key.toUpperCase().charCodeAt(0);
    }
    e.key = key;
    e.which = e.keyCode = which;
    return e;
}
function keypress(key) {
    var e = $.Event("keypress");
    e.key = key;
    e.which = e.keyCode = 0;
    return e;
}
function shortcut({
    ctrl = false,
    alt = false,
    shift = false,
    which,
    key
}) {
    var doc = $(document.documentElement || window);
    if (typeof which === 'string') {
        key = which;
        which = key.toUpperCase().charCodeAt(0);
    }
    doc.trigger(keydown(ctrl, alt, shift, which, key));
    doc.trigger(keypress(key));
}

您可以使用快捷键来触发 keydown 和 keypress：

shortcut({ctrl: true, alt: true, which: 'r'});

如果你有监听器做不同的事情（我的 jQuery 终端测试中有这个）；

本机代码：

 function shortcut({chr, ctrlKey = false, altKey = false}) {
     var lowerChr = chr.toLowerCase();
     var upperChr = chr.toUpperCase();
     var keydownCode = upperChr.charCodeAt(0);
     var e = new KeyboardEvent("keydown", {
         key: lowerChr,
         code: "Key" + upperChr,
         ctrlKey,
         altKey,
         keyCode: keydownCode,
         which: keydownCode
     });
     var keypressCode = lowerChr.charCodeAt(0);
     document.documentElement.dispatchEvent(e);
     var e = new KeyboardEvent("keypress", {
         key: lowerChr,
         ctrlKey,
         altKey,
         charCode: keypressCode,
         keyCode: keypressCode,
         which: keypressCode
     });
     document.documentElement.dispatchEvent(e);
 }