javascript的搜索 麻烦高手帮看看
下面着些代码是一个javascript的搜索　但是为什么第一次点击button触发的也是本页呢　代码如下：   <script   type= "text/javascript ">
// <![CDATA[
function   GetObj(objName){
  if(document.getElementById){
    return   eval( 'document.getElementById( " '   +   objName   +   ' ") ');
  }else   if(document.layers){
    return   eval( "document.layers[ ' "   +   objName   + " '] ");
  }else{
    return   eval( 'document.all. '   +   objName);
  }
}
function   ss(fn){
if(fn.k.value   ==   " "){
alert( "请输入搜索的内容！ ")
return   false;
}else
{
window.open( "web.aspx?l= "+   fn.i_k.name   + "&i_x= "   +fn.i_x.value+   "&value= "   +   fn.k.value+   "&i_aa= "   +   fn.i_aa.value);
}

}
function   sss(fn){
if(fn.k.value   ==   " "){
alert( "请输入搜索的内容！ ")
return   false;
}else
{
window.open( "webcp.aspx?l= "+   fn.i_k.name   + "&i_x= "   +fn.i_x.value+   "&value= "   +   fn.k.value+   "&i_aa= "   +   fn.i_aa.value);
}

}
function   sChange(obj)
{
  if   (obj.value== " "){
document.all.i_x.style.display= "none ";
}else{
document.all.i_x.style.display= "inline "
}
}
function   s_chg(td_now,   fn)
{
for(var   i   =   1;   i   <   8;   i++){
eval( "var   s_td_ "   +   i   + "=   GetObj( 's_td_ "+i+ " ') ");
}
var   lc   =   GetObj( "lc ");
var   i_ms   =   GetObj( "i_ms ");
var   i_btm   =   GetObj( "i_btm ");
var   i_k   =   GetObj( "i_k ");
var   i_kw   =   GetObj( "i_kw ");


if(td_now.id   ==   "s_td_1 ")//公司姓名
{
lc.style.display   =   "none ";
i_ms.style.width   =   "400px ";
i_btm.width   =   "150px ";
i_btm.innerHTML   =   ' <select   name= "i_aa "   onchange= "sChange(this) "   style= "display:none "> </select> <select   name= "i_x "     style= "display:none "> </select> <input   id= "btn_i "   type= "submit "   value= "搜   索 "   class= "i_btn "   onClick= "ss(f);return   false; "> ';
fn.i_k.name   =   "k1 ";
}
if(td_now.id   ==   "s_td_2 ")//区域位置
{
lc.style.display   =   "none ";
i_ms.style.width   =   "350px ";
i_btm.width   =   "200px ";
i_btm.innerHTML   =   ' <select   name= "i_aa "   onchange= "sChange(this) "   style= "display:none "> </select> <select   name= "i_x "   > <option   value= "全市搜索 "> 全市搜索 </option> <option   value= "兴隆台区 &