function isEmail(str){var reg = /^([.a-zA-Z0-9_-])+@([a-zA-Z0-9_-])+((\.[a-zA-Z0-9_-]{2,3}){1,2})$/; return reg.test(str);}
function isNull(str){if ( str == "" ) return true; var regu = "^[ ]+$"; var re = new RegExp(regu); return re.test(str);}
$(function (){	
	$("#gmail").focus(function(){$(this).val(''); })
	.blur(function(){ if(isNull($("#gmail").val())){ $(this).val('您的Email'); }  });
	$("#emailsubmit").click(function(){
		var $email = $("#gmail").val();
		$email = $email.replace('您的Email','');
		//alert($email);
		if(isNull($email) || !isEmail($email) ){
			alert('Email填写有误');
		}else{
			$.post('giftEmail.php', {'gmail':$email } , function(data){ if(!isNull(data)){ alert(data);}  });
		}
	});	
})