如何在Javascript中映射移动触摸事件以模拟向上/向下按键？

我有两个类似按钮的div元素，我想映射到键盘上的左右箭头键

<div id="leftBtn" ontouchstart="simKeyDown(event, LEFT_KEYCODE);" ontouchend="simKeyUp(event, LEFT_KEYCODE);" onmspointerup="simKeyUp(event, LEFT_KEYCODE);" onmspointerdown="simKeyDown(event, LEFT_KEYCODE);"><img src="../images/left.png"></div>

<div id="rightBtn" ontouchstart="simKeyDown(event, RIGHT_KEYCODE);" ontouchend="simKeyUp(event, RIGHT_KEYCODE);" onmspointerup="simKeyUp(event, RIGHT_KEYCODE);" onmspointerdown="simKeyDown(event, RIGHT_KEYCODE);"><img src="../images/right.png"></div>

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我在最后一个要将触摸事件映射到按键的功能中卡住了。任何帮助或指导都将不胜感激。我也愿意接受其他实现方法。

如果按下左/右键，您可以使用两个变量来跟踪。基于此，您可以在画布渲染动画方法中检查这些值，以处理必要的操作。 例如：

无论何时调用keyUp或keyDown方法，都可以将变量更新为true/false

//Key codes for simulating key events
var LEFT_KEYCODE = 37; //Left cursor key
var RIGHT_KEYCODE = 39; //Right cursor key

var LEFT_KEY_PRESSED = false;
var RIGHT_KEY_PRESSED = false;

//Simulate a key up event
function simKeyUp(e, keyCode) {
    //Suppress the default action
    e.preventDefault();

    //Send the event as a key up event
    queueKeyboardEvent('KeyUp', keyCode);
}

//Simulate a key down event
function simKeyDown(e, keyCode) {
    //Suppress the default action
    e.preventDefault();

    //Send the event as a key down event
    queueKeyboardEvent('KeyDown', keyCode);
}

function queueKeyboardEvent(eventType, keyCode) {
  if (eventType === 'KeyUp') {
    if (keyCode == LEFT_KEYCODE) {
      LEFT_KEY_PRESSED = true
    }
    
    if (keyCode == RIGHT_KEYCODE) {
      RIGHT_KEY_PRESSED = true
    }
  }

  if (eventType === 'KeyDown') {
    if (keyCode == LEFT_KEYCODE) {
      LEFT_KEY_PRESSED = false
    }
    
    if (keyCode == RIGHT_KEYCODE) {
      RIGHT_KEY_PRESSED = false
    }
  }

}

如果您有任何requestframe方法或动画方法，您可以检查这些值并执行所需的更新

例如：

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假设您只是想将击键发送到页面上的文本表单或类似的表单，请查看以下线程：您不能将按键发送到操作系统。我不会将其发送到输入字段。左键和右键将控制画布元素。可能是这样？

var LEFT_KEY_PRESSED = false;
var RIGHT_KEY_PRESSED = false;

//Key codes for simulating key events
var LEFT_KEYCODE = 37; //Left cursor key
var RIGHT_KEYCODE = 39; //Right cursor key

var LEFT_KEY_PRESSED = false;
var RIGHT_KEY_PRESSED = false;

//Simulate a key up event
function simKeyUp(e, keyCode) {
    //Suppress the default action
    e.preventDefault();

    //Send the event as a key up event
    queueKeyboardEvent('KeyUp', keyCode);
}

//Simulate a key down event
function simKeyDown(e, keyCode) {
    //Suppress the default action
    e.preventDefault();

    //Send the event as a key down event
    queueKeyboardEvent('KeyDown', keyCode);
}

function queueKeyboardEvent(eventType, keyCode) {
  if (eventType === 'KeyUp') {
    if (keyCode == LEFT_KEYCODE) {
      LEFT_KEY_PRESSED = true
    }
    
    if (keyCode == RIGHT_KEYCODE) {
      RIGHT_KEY_PRESSED = true
    }
  }

  if (eventType === 'KeyDown') {
    if (keyCode == LEFT_KEYCODE) {
      LEFT_KEY_PRESSED = false
    }
    
    if (keyCode == RIGHT_KEYCODE) {
      RIGHT_KEY_PRESSED = false
    }
  }

}

function animate() {

  if (LEFT_KEY_PRESSED ) {
    player.left++
  }

  if (RIGHT_KEY_PRESSED ) {
    player.right++
  }

}