var blnerrfound ;

function validlargelength(item,len){
	return(item.length>=len);
}

function validlesslength(item,len){
	return(item.length<=len);
}

function validequallengthii(item,len){
	return(item.length==len);
}

function validnumber(item){
	etext=item;
	elen=item.length;
	
	for (i=0;i<=elen-1;i++){
  		aa=etext.charat(i)
  		if (aa<'0'||aa>'9') return false;
  	}
  	return true;
}

function validphone(item){
	if (item.length<0)
   		return false;
 	if (validlargelength(item,7))
   		return true
}

function validemail(item){
	var etext
	var elen
	var i
	var aa
	etext=item
	elen=etext.length
	if (elen<5)
		return true;
	i= etext.indexof("@",0)
	if (i==0 || i==-1 || i==elen-1)
		return true;
	else{
		if (etext.indexof("@",i+1)!=-1)
			return true;
		}
	if (etext.indexof("..",i+1)!=-1)
		return true;
	i=etext.indexof(".",0)
	if (i==0 || i==-1 || etext.charat(elen-1)=='.')
		return true;
	if ( etext.charat(0)=='-' ||  etext.charat(elen-1)=='-')
		return true;
	if ( etext.charat(0)=='_' ||  etext.charat(elen-1)=='_')
		return true;
	for (i=0;i<=elen-1;i++){
		aa=etext.charat(i)
		if (!((aa=='.') || (aa=='@') || (aa=='-') ||(aa=='_') || (aa>='0' && aa<='9') || (aa>='a' && aa<='z') || (aa>='a' && aa<='z')))
			return true;
	}
	return false;
}

function validpasswd(item,item1){
	 return(item.value==item1.value);
}

 function error(text){
	 if(blnerrfound) return;
	 window.alert(text);
	 blnerrfound=true;
}

function validata(){
	blnerrfound = false;
	var g_name = document.form1.g_name;
	var g_title   = document.form1.g_title;
	var g_content = document.form1.g_content;
	
	if(!validlargelength(g_name.value,1)){
	    error("请输入用户名！");
		g_name.focus();
	}else if(!validlargelength(g_title.value,1)){
		error("请输入留言的主题！");
		g_title.focus();
	}else if(!validlargelength(g_content.value,1)){
		error("请输入留言的内容！");
		g_content.focus();
	}

  return !blnerrfound;
}