Question

setInterval(mouse, 20);  

function mouse(){
        if(onMouseDown == true){
            //Code for when you are holding mouse down
        }else{
            //Code for when the mouse isn't being held
        }
    }

这是我的代码的基本思路。当按住鼠标左键时，我希望它执行设置代码，然后当鼠标没有按下时，它会执行另一个任务。我该怎么做呢。谢谢:)）

Answer 1

function detectLeftButton(evt) {
   evt = evt || window.event;
   var btn = evt.which || evt.button;
   return (btn == 1);
}
document.onmousedown = function() {
   if(detectLeftButton(this.event)) {
   // Code when mouse is down
   }
}

document.onmouseup = function() {
   if(detectLeftButton(this.event)) {
   // Code when mouse is not held
   }
}

在上面的代码中，当人在网页的任何地方按下鼠标左键时，代码将被运行，当他按下它时，将执行另一组代码。 Fiddle (updated)

了解详情here。

希望有所帮助。

Answer 2

使用mousedown和mouseup事件以及setInterval / clearInterval

(function(){
   var downTimer = null;
   var upTimer = null;
   function runWhileDown(){
      //code to run while mouse is down
   }
   function runWhileUp(){
      //code to run while mouse is up
   }
   document.addEventListener("mousedown",function(){
      //Stop the runWhileUp code from running
      if(upTimer) clearInterval(upTimer);
      //make sure the previous interval is stopped
      if(downTimer) clearInterval(downTimer);
      //start the new timer
      downTimer = setInterval(runWhileDown,20);
   });
   document.addEventListener("mouseup",function(){
      //Stop the runWhileDown code from running
      if(downTimer) clearInterval(downTimer);
      //make sure the previous interval is stopped
      if(upTimer) clearInterval(upTimer);
      //start the new timer
      upTimer = setInterval(runWhileUp,20);
   });
   //If you need the runWhileUp code to run at the start
   upTimer = setInterval(runWhileUp,20);
})();

JSFiddle

Javascript onMouseDown函数，在您单击左键时进行测试

2 个答案: