<!--
function CheckForm()
{
if (search_form.keyword.value == ""||search_form.keyword.value == "请输入产品名称"||search_form.keyword.value == "请输入企业名称或主营或地址"||search_form.keyword.value == "请输入你要搜索的求购信息"||search_form.keyword.value == "请输入展会名称")
{
alert("关键字不能为空！");
search_form.keyword.focus();
return false;
}
}

function top_change(s){
var s;
if(s=="1"){
top1.innerText="产品";
top1.className="curstyle";	
top2.innerHTML="企业";	
top2.className="nocurstyle";
top3.innerHTML="买家";	
top3.className="nocurstyle";
top4.innerHTML="展会";	
top4.className="nocurstyle";

search_form.action="http://www.rayp.com/list.php";
var v = search_form.keyword.value;
if(trim(v) == "" || v.substring(0,3) =="请输入") search_form.keyword.value="请输入产品名称";
}
if(s=="2"){
top1.innerText="产品";
top1.className="nocurstyle";	
top2.innerHTML="企业";	
top2.className="curstyle";
top3.innerHTML="买家";	
top3.className="nocurstyle";
top4.innerHTML="展会";	
top4.className="nocurstyle";
search_form.action="http://www.rayp.com/trade.php";
var v = search_form.keyword.value;
if(trim(v) == "" || v.substring(0,3) =="请输入") search_form.keyword.value="请输入企业名称或主营或地址";
}
if(s=="3"){
top1.innerText="产品";
top1.className="nocurstyle";	
top2.innerHTML="企业";	
top2.className="nocurstyle";
top3.innerHTML="买家";	
top3.className="curstyle";
top4.innerHTML="展会";	
top4.className="nocurstyle";
search_form.action="http://www.rayp.com/buyer.php";
var v = search_form.keyword.value;
if(trim(v) == "" || v.substring(0,3) =="请输入") search_form.keyword.value="请输入你要搜索的求购信息";
}
if(s=="4"){
top1.innerText="展会";
top1.className="nocurstyle";	
top2.innerHTML="企业";	
top2.className="nocurstyle";
top3.innerHTML="买家";	
top3.className="nocurstyle";
top4.innerHTML="展会";	
top4.className="curstyle";
search_form.action="http://www.rayp.com/exb.php";
var v = search_form.keyword.value;
if(trim(v) == "" || v.substring(0,3) =="请输入") search_form.keyword.value="请输入展会名称";
}

}
function trim(inputString) {
return inputString.replace(/^ +/,"").replace(/ +$/,"");
}
//-->