我的第一个javascript网页作业

   1:  <html>
   2:  <title>    
   3:   
   4:  </title>
   5:      <body>
   6:       <style type="text/css">
   7:                  #block{
   8:                  background-color:green;
   9:                  font-size:9pt;
  10:                  padding:30px;
  11:                  color:white;
  12:                  100px;
  13:                  height:120px;
  14:                  position:absolute;
  15:                  }
  16:        </style>
  17:        <div id="block"></div>  
  18:        
  19:        <script>
  20:              function down(event){
  21:   
  22:                  var x = event.clientX;
  23:                  var y = event.clientY;  
  24:                  var oleft = document.getElementById('block').offsetLeft;
  25:                  var otop  = document.getElementById('block').offsetTop;
  26:                  offx = x - oleft;
  27:                  offy = y - otop;
  28:                   
  29:                  document.onmousemove = move;
  30:                  document.onmousemup  = up;
  31:                 
  32:              }  
  33:              function move(event){
  34:                  var x = event.clientX;
  35:                  var y = event.clientY;                
  36:                   
  37:                  document.getElementById('block').style.left = x - offx +'px';  
  38:                  document.getElementById('block').style.top  = y - offy +'px';
  39:                  
  40:                  document.onmouseup = up;
  41:              }  
  42:              function up(){
  43:                  document.onmouseup = null;
  44:                  document.onmousemove = null;
  45:              }
  46:              window.onload = function(){
  47:                  document.onmousedown = down;
  48:              }
  49:          </script>     
  50:        
  51:   
  52:      </body>
  53:      
  54:   
  55:  </html>
原文地址:https://www.cnblogs.com/ppazhang/p/3250500.html