是否可以在JavaScript中以编程方式模拟按键事件?
当前回答
基于@aljgom的回答:
这对我来说很有效。而不是像aljgom建议的那样将事件分派给元素,而是将它分派给文档。
document.dispatchEvent(new KeyboardEvent("keydown", { key: "c" }));
其他回答
你可以在EventTarget(元素,窗口,文档等)上分派键盘事件,如下所示:
element.dispatchEvent(new KeyboardEvent('keydown', {'key': 'a'}));
但是,dispatchEvent可能不会更新输入字段值,也可能不会触发常规键盘按下的行为,这可能是因为Event的原因。itrusted property,我不知道是否有办法绕过
但是你也可以通过设置输入值来改变输入。
element.value += "a";
例子:
let element = document.querySelector('input'); 元素。Onkeydown = e =>警报(e.key); changeValButton。Onclick =() =>元素。Value += "a"; dispatchButton。Onclick = () => { 元素。dispatchEvent(new KeyboardEvent('keydown', {'key': 'a'})); } <输入/ > <button id="dispatchButton">按下分派事件</button> <button id="changeValButton">按下按钮更改值</button> . </button id="changeValButton">
您可以根据需要向事件添加更多属性,如本答案所示。看一下KeyboardEvent文档
element.dispatchEvent(new KeyboardEvent("keydown", {
key: "e",
keyCode: 69, // example values.
code: "KeyE", // put everything you need in this object.
which: 69,
shiftKey: false, // you don't need to include values
ctrlKey: false, // if you aren't going to use them.
metaKey: false // these are here for example's sake.
}));
此外,由于keypress已弃用,您可以使用keydown + keyup,例如:
element.dispatchEvent(new KeyboardEvent('keydown', {'key':'Shift'} ));
element.dispatchEvent(new KeyboardEvent( 'keyup' , {'key':'Shift'} ));
对于使用ReactJS的页面,这是一个尝试模拟键盘行为的线程
只要用户按下有问题的键,你就可以存储对该even的引用,并将其用于任何HTML其他元素:
EnterKeyPressToEmulate<input class="lineEditInput" id="addr333_1" type="text" style="width:60%;right:0%;float:right" onkeydown="keyPressRecorder(event)"></input> TypeHereToEmulateKeyPress<input class="lineEditInput" id="addr333_2" type="text" style="width:60%;right:0%;float:right" onkeydown="triggerKeyPressOnNextSiblingFromWithinKeyPress(event)"> Itappears Here Too<input class="lineEditInput" id="addr333_3" type="text" style="width:60%;right:0%;float:right;" onkeydown="keyPressHandler(event)"> <script> var gZeroEvent; function keyPressRecorder(e) { gZeroEvent = e; } function triggerKeyPressOnNextSiblingFromWithinKeyPress(TTT) { if(typeof(gZeroEvent) != 'undefined') { TTT.currentTarget.nextElementSibling.dispatchEvent(gZeroEvent); keyPressHandler(TTT); } } function keyPressHandler(TTT) { if(typeof(gZeroEvent) != 'undefined') { TTT.currentTarget.value+= gZeroEvent.key; event.preventDefault(); event.stopPropagation(); } } </script>
如果你创建自己的事件,你可以设置keyCode,你可以从任何真实的键盘事件复制现有的参数(忽略目标,因为它的工作dispatchEvent)和:
ta = new KeyboardEvent('keypress',{ctrlKey:true,key:'Escape'})
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);
只需使用CustomEvent
Node.prototype.fire=function(type,options){
var event=new CustomEvent(type);
for(var p in options){
event[p]=options[p];
}
this.dispatchEvent(event);
}
4 ex想模拟ctrl+z
window.addEventListener("keyup",function(ev){
if(ev.ctrlKey && ev.keyCode === 90) console.log(ev); // or do smth
})
document.fire("keyup",{ctrlKey:true,keyCode:90,bubbles:true})
这里有一个真正有用的库:https://cdn.rawgit.com/ccampbell/mousetrap/2e5c2a8adbe80a89050aaf4e02c45f02f1cc12d4/tests/libs/key-event.js
我不知道它是从哪里来的,但它是有帮助的。它向window添加了一个.simulate()方法。你可以简单地用KeyEvent。simulate(0,13)用于模拟enter或KeyEvent。为'Q'模拟(81,81)。
我在https://github.com/ccampbell/mousetrap/tree/master/tests上买的。