function checkEmail(emailStr) {
   if (emailStr.length == 0) {
       return true;
   }
   var emailPat=/^(.+)@(.+)$/;
   var specialChars="\\(\\)<>@,;:\\\\\\\"\\.\\[\\]";
   var validChars="\[^\\s" + specialChars + "\]";
   var quotedUser="(\"[^\"]*\")";
   var ipDomainPat=/^(\d{1,3})[.](\d{1,3})[.](\d{1,3})[.](\d{1,3})$/;
   var atom=validChars + '+';
   var word="(" + atom + "|" + quotedUser + ")";
   var userPat=new RegExp("^" + word + "(\\." + word + ")*$");
   var domainPat=new RegExp("^" + atom + "(\\." + atom + ")*$");
   var matchArray=emailStr.match(emailPat);
   if (matchArray == null) {
       return false;
   }
   var user=matchArray[1];
   var domain=matchArray[2];
   if (user.match(userPat) == null) {
       return false;
   }
   var IPArray = domain.match(ipDomainPat);
   if (IPArray != null) {
       for (var i = 1; i <= 4; i++) {
          if (IPArray[i] > 255) {
             return false;
          }
       }
       return true;
   }
   var domainArray=domain.match(domainPat);
   if (domainArray == null) {
       return false;
   }
   var atomPat=new RegExp(atom,"g");
   var domArr=domain.match(atomPat);
   var len=domArr.length;
   if ((domArr[domArr.length-1].length < 2) ||
       (domArr[domArr.length-1].length > 3)) {
       return false;
   }
   if (len < 2) {
       return false;
   }
   return true;
}
function chk_form(){
	var err_msg="";
	var n=[];
	var f=["body","kanji0","kanji1","furi0","furi1","email"];
	var k=["問い合わせ本文","苗字(漢字)","名前(漢字)","苗字(かな)","名前(かな)","メールアドレス"];
	for(var i=0;i<k.length;i++){
		if(document.ff["p_"+f[i]].value.length>0){continue;}
		err_msg+="*"+k[i]+"\n";
		n[n.length]=i;
	}
	if(n.length==0){
		if(!checkEmail(document.ff["p_email"].value)){
			alert("入力されたメールアドレスは無効な形式ですのでチェックしてください。");
			return false;
		}else{
			return true;
		}
	}else{
		alert("【注意】\n\n下記の項目は必須項目です。\n必ず入力してください。\n\n"+err_msg);
		return false;
	}
}