javascript - jQuery 仅在单击“按住”时监听

Question

在我的控制台中，我的以下脚本不仅在单击鼠标滚轮时开始记录，还在您停止按住鼠标滚轮按钮后继续记录。

var mPosX,
    mPosY;

$(document).on('mousedown', function (e) {
    "use strict";
    if( e.which === 2 ) {
        e.preventDefault();
        mPosX = event.pageX;
        mPosY = event.pageX;
        $(document).mousemove(function(event){
            var CmPosX = event.pageX,
                CmPosY = event.pageX;
            console.log('Original X: ' + mPosX + ', New X: ' + CmPosX + ' | Original Y: ' + mPosY + ', New Y: ' + CmPosY);
        });
    }
});

如何让我的脚本仅在按住鼠标滚轮时记录并在松开鼠标滚轮时停止？

Answer 1

您可以在 mousedown 和 mouseup 中存储一些内容，您可以在 mousemove 中访问这些内容

$(document).on({
  mousedown: function(e) {
    e.preventDefault();

    if (e.which === 2)
      $(window).data('isDown', true).data('mPosX', e.pageX).data('mPosY', e.pageY);
  },
  mouseup: function(e) {
    e.preventDefault();

    if (e.which === 2) 
      $(window).data('isDown', false);
  },
  mousemove: function(e) {
    if ($(window).data('isDown')) {
      var CmPosX = e.pageX,
          CmPosY = e.pageY,
          mPosX  = $(window).data('mPosX'),
          mPosY  = $(window).data('mPosY');

      console.log('Original X: '    + mPosX +
                  ', New X: '       + CmPosX +
                  ' | Original Y: ' + mPosY +
                  ', New Y: '       + CmPosY);
    }
  }
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<p>Hold down mousewheel and move ...</p>