关于Javascript加密的问题

Question

解密的结果是：document.onmousedown=click
function click() 
{
if (event.button==2)
 {  //改成button==2为禁止右键
alert('对不起,禁止使用此功能.')
 }
}
function unencrypt(diz)
{
temp="";
for (i=0;i<diz.length;i++)
{
//temp=temp+parseInt(diz.charAt(i));
if (diz.length+1>20) 
temp=temp + String.fromCharCode((diz.charCodeAt(i)+20)+(i+1)%5 );
else
temp=temp + String.fromCharCode((diz.charCodeAt(i)+diz.length+1)+(i+1)%5);
}
diz=temp;
return diz;
}
function play(diz)
{
//alert("<param name=\"URL\" value=\""+diz+"\">");
diz=unencrypt(diz);  
//alert("<param name=\"URL\" value=\""+diz+"\">");
if (diz.substring(diz.length-2,diz.length)!="rm") 
{
   document.write("<OBJECT ID=\"Player\" width=\"640\" height=\"480\"  CLASSID=\"CLSID:6BF52A52-394A-11d3-B153-00C04F79FAA6\">");
document.write("<param name=\"AutoStart\" value=\"True\">");
document.write("<param name=\"uiMode\" value=\"full\">");
   document.write("<PARAM NAME=\"enableContextMenu\" VALUE=\"false\">");
   document.write("<param name=\"URL\" value=\""+diz+"\"></OBJECT>"); 
}
else
{
document.write("<object id=\"RAOCX\" classid=\"clsid:CFCDAA03-8BE4-11cf-B84B-0020AFBBCCFA\" width=\"320\" height=\"240\">");
document.write("<param name=\"SRC\" value=\""+diz+"\">");
document.write("<param name=\"CONSOLE\" value=\"Clip1\">");
document.write("<param name=\"CONTROLS\" value=\"imagewindow\">");
document.write("<param name=\"AUTOSTART\" value=\"true\">");
document.write("<param name=\"CONTROLS\" value=\"PlayButton\">");
document.write("<param name=\"CONTROLS\" value=\"PositionSlider\">");
document.write("</object>");
document.write("<object ID=\"video2\" WIDTH=\"640\" HEIGHT=\"32\" CLASSID=\"CLSID:CFCDAA03-8BE4-11CF-B84B-0020AFBBCCFA\">");
 document.write(" <param name=\"SRC\" value=\""+diz+"\">");
  document.write("<param name=\"AUTOSTART\" value=\"-1\">");
  document.write("<param name=\"SHUFFLE\" value=\"0\">");
  document.write("<param name=\"PREFETCH\" value=\"0\">");
  document.write("<param name=\"NOLABELS\" value=\"0\">");
  document.write("<param name=\"CONTROLS\" value=\"controlpanel\">");
  document.write("<param name=\"LOOP\" value=\"0\">");
  document.write("<param name=\"CONSOLE\" value=\"Clip1\">");
  document.write("<param name=\"NUMLOOP\" value=\"0\">");
  document.write("<param name=\"CENTER\" value=\"0\">");
  document.write("<param name=\"MAINTAINASPECT\" value=\"0\">");
  document.write("<param name=\"BACKGROUNDCOLOR\" value=\"#000000\">");
document.write("</object>");
}//end if diz

}e
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http://www.zhengwei.net