急！！请问怎么实现在框架上放一个按钮能控制缩放框架

/////////a.html<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Frameset//EN" "http://www.w3.org/TR/html4/frameset.dtd">
<html>
<head>
<title>abcdefg</title>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
</head><frameset name='a' id='a' cols='120,8,*' rows='*' frameSpacing=0 frameborder='no' border='0' scrolling=yes>  <FRAME name='b' id='b' src='b.html'   SCROLLING='NO'  MARGINWIDTH=0 MARGINHEIGHT=0  noresize frameborder="NO">
  <FRAME name='m' src='m.html' scrolling='NO'  MARGINWIDTH=0 MARGINHEIGHT=0 frameborder='NO' noresize>
  <FRAME name='c' src="c.html" frameBorder=0 MARGINWIDTH=0 MARGINHEIGHT=0 scrolling="yes" noresize>
</frameset>
<noframes><body></body></noframes>
</html>
///b.html
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312"></head>
<body leftmargin="0" topmargin="0" marginwidth="0" marginheight="0"  class=middleStyle>xxxxxxxxxxxxxxxxxxxxxxxx
</body>
</html>
///////m.html<html>
<head><script language="JavaScript">
<!--var Bln=true;
var abledMoveFrame=true;function manage_tool(){
    if (getAbledMoveFrame()){
if(window.parent.a.cols=="120,8,*"){
frameshow.src="pointRight_1.gif";
manage_tree.title="显示工具栏"
window.parent.a.cols="0,8,*";
Bln=false;
}
else{
frameshow.src="pointLeft_1.gif";
manage_tree.title="隐藏工具栏"
window.parent.a.cols="120,8,*";
Bln=true;
}
    }
}function setAbledMoveFrame(){
   abledMoveFrame = false;
}function getAbledMoveFrame(){
   return abledMoveFrame;
}function point1_over(){
if(Bln==true){
frameshow.src="pointLeft_1.gif";
}
else{
frameshow.src="pointRight_1.gif";
}
}
function point1_out(){
if(Bln==true){
frameshow.src="pointLeft_2.gif";
}
else{
frameshow.src="pointRight_2.gif";
}
  }
  
//-->  
</script>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312"></head>
<body background="bgline1.gif" leftmargin="0" topmargin="0" marginwidth="0" marginheight="0"  class=middleStyle><table width="10" border="0" height="100%" cellpadding="0" cellspacing="0" align="left"  class=middleStyle>
  <tr>
    <td height="20">&nbsp;</td>
  </tr>
  <tr  align="center" height="100%"> 
    <td height="100%" > 
      <div STYLE='cursor:hand' id=manage_tree onclick="manage_tool();" 
       onMouseover="point1_over()"
       onMouseout="point1_out()" title=隐藏工具栏>
  <img id=frameshow src="pointLeft_1.gif" width="8" ></div>
    </td>
    
  </tr>  
  <tr>
    <td height="28">&nbsp; </td>
  </tr>
</table>
</body>
</html>
///c.html<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312"></head>
<body background="images/bgline1.gif" leftmargin="0" topmargin="0" marginwidth="0" marginheight="0"  class=middleStyle>xxxxxxxxxxxxxxxxxxxxxxxx
</body>
</html>
////以上的文件中，m.html里的javascript是控制框架的缩放.