是否可以在JavaScript中以编程方式模拟按键事件?
当前回答
js全屏切换方法的最佳方法:
function toggleFullScreen() {
if (!document.fullscreenElement) {
document.documentElement.requestFullscreen();
} else if (document.exitFullscreen) {
document.exitFullscreen();
}
}
其他回答
对于那些感兴趣的人,您可以可靠地重新创建键盘输入事件。为了更改输入区域中的文本(移动游标,或通过输入字符移动页面),必须严格遵循DOM事件模型:http://www.w3.org/TR/DOM-Level-3-Events/#h4_events-inputevents
该模型应该做到:
焦点(使用目标设置在DOM上分派)
然后对于每个字符:
keydown(在DOM上分派) Beforeinput(如果它是一个文本区域或输入,在目标分派) 按键(在DOM上分派) 输入(如果是文本区域或输入,则在目标处分派) 改变(如果它是一个选择,在目标分派) keyup(在DOM上分派)
然后,可选的大多数:
模糊(随目标设置在DOM上分派)
这实际上是通过javascript改变页面中的文本(不修改值语句),并适当地设置任何javascript侦听器/处理程序。如果你把顺序弄乱了,javascript就不会按适当的顺序触发,输入框中的文本不会改变,选择不会改变,或者光标不会移动到文本区域的下一个空格。
不幸的是,代码是为雇主写的,所以我不能分享它,但这绝对是可能的,但你必须以正确的顺序为每个元素重新创建整个关键输入“堆栈”。
编辑:我不是这个答案的原始海报,但我已经测试过了,我不能让它更新输入字段。下面是一个代码片段,其中的代码供其他人尝试或查看
let element = document.querySelector('input'); element.onkeydown = e => console.log('keydown on element: ' + e.key); document.onkeydown = e => console.log('keydown on document: ' + e.key + " " + e.target); dispatchButton.onclick = () => dispatchKey(element, 'a') dispatchKey = (target, key) => { let dom = document; // focus (dispatched on the DOM with the target set) let ev = new Event('focus', {target: target}); // this part seems to not work? when logging the // target in the onkeypress function it shows `document` instead of `input` // I also tried these and got the same behavior // ev.target = target; // and // Object.defineProperty(ev, 'target', {writable: false, value: target}); dom.dispatchEvent(ev); // keydown (dispatched on the DOM) dom.dispatchEvent(new KeyboardEvent('keydown', {'key': key, target: target})); // beforeinput (dispatched at the target if it's a textarea or input) target.dispatchEvent(new Event('beforeinput')); // keypress (dispatched on the DOM) dom.dispatchEvent(new KeyboardEvent('keypress', {'key': key})); // input (dispatched at the target if it's a textarea or input) target.dispatchEvent(new Event('input')); // change (dispatched at the target if it's a select) // keyup (dispatched on the DOM) dom.dispatchEvent(new KeyboardEvent('keyup', {'key': key})); // Then, optionally for most: // blur (dispatched on the DOM with the target set) dom.dispatchEvent(new Event('blur', {target: target})); console.log('dispatched'); } <input/> <button id="dispatchButton">Press to dispatch events </button>
这种方法支持跨浏览器更改键代码的值。 源
var $textBox = $("#myTextBox");
var press = jQuery.Event("keypress");
press.altGraphKey = false;
press.altKey = false;
press.bubbles = true;
press.cancelBubble = false;
press.cancelable = true;
press.charCode = 13;
press.clipboardData = undefined;
press.ctrlKey = false;
press.currentTarget = $textBox[0];
press.defaultPrevented = false;
press.detail = 0;
press.eventPhase = 2;
press.keyCode = 13;
press.keyIdentifier = "";
press.keyLocation = 0;
press.layerX = 0;
press.layerY = 0;
press.metaKey = false;
press.pageX = 0;
press.pageY = 0;
press.returnValue = true;
press.shiftKey = false;
press.srcElement = $textBox[0];
press.target = $textBox[0];
press.type = "keypress";
press.view = Window;
press.which = 13;
$textBox.trigger(press);
由于在控制台上下文中易于使用,它曾经是单行的。但可能还是有用的。
Var pressthiskey = "q"/* <——q为例*/; var e = new事件("keydown"); E.key =按下这个键; e.keyCode = e.key.charCodeAt(0); e.which = e.keyCode; e.altKey = false; e.ctrlKey = true; e.shiftKey = false; e.metaKey = false; E.bubbles = true; document.dispatchEvent (e);
一个非jquery版本,工作在webkit和gecko:
var keyboardEvent = document.createEvent('KeyboardEvent'); var initMethod = typeof keyboardEvent.initKeyboardEvent !== 'undefined' ? 'initKeyboardEvent' : 'initKeyEvent'; keyboardEvent[initMethod]( 'keydown', // event type: keydown, keyup, keypress true, // bubbles true, // cancelable window, // view: should be window false, // ctrlKey false, // altKey false, // shiftKey false, // metaKey 40, // keyCode: unsigned long - the virtual key code, else 0 0, // charCode: unsigned long - the Unicode character associated with the depressed key, else 0 ); document.dispatchEvent(keyboardEvent);
让它工作的关键部分是认识到charCode, keyCode和这些都是不推荐的方法。因此,如果处理按键事件的代码使用这三个中的任何一个,那么它将收到一个伪答案(例如,默认值为0)。
只要使用非弃用的方法(如key)访问按键事件,就应该没问题。
为了完成,我添加了触发事件的基本Javascript代码:
const rightArrowKey = 39 const event = new KeyboardEvent('keydown',{'key':rightArrowKey}) document.dispatchEvent(事件)