function checkdata()
{ 
var user=document.getElementById("username")
var uEmpt=document.getElementById("u_empty")
if(user){
if(user.value==""){
uEmpt.innerHTML='*用户名和密码不能为空！'
user.focus();
return false;
}
else{
uEmpt.innerHTML=''
}
}
var mypoint=document.getElementById("mypoint")
var points=mypoint.getElementsByTagName("input")
var chk=false
for(i=0;i<points.length-1;i++){
if(points[i].checked==true){
chk++
break;
}
}
var pointEmpt=document.getElementById("point_empty")
if(chk<1){
pointEmpt.innerHTML='*请您为该商家评分！'
return false;
}
else{
pointEmpt.innerHTML=''
}
var myreview=document.getElementById("myreview")
var reviewEmpt=document.getElementById("review_empty")
if(myreview.value==""){
reviewEmpt.innerHTML="*评论内容不能为空！"
myreview.focus();
return false;
}
else{
reviewEmpt.innerHTML=""
}
return true;
} 

function checkkey(){
var mykeyword=document.getElementById("mykey")
var keyEmpt=document.getElementById("keyword_empty")
if(mykeyword.value==""){
keyEmpt.innerHTML="*请输入查询关键词!"
return false;
}
}

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