ประกาศตัวแปร $i++ ใน php 5.4.x ประกาศไงไม่ให้มัน error ครับ !

	$i == 0;
	while($objResult = mysql_fetch_array($objQuery)){
		$nrReply = mysql_num_rows(mysql_query("SELECT * FROM other_webboard_reply WHERE wbID = '".$objResult['wbID']."'"));
		$i++;
		$bg = ($i%2 == 0) ? "#e0eee0" : "";
		if((time()-86400) < $objResult['wbDate']){
		      $img = '../administrator/images/icon/p_new.png';
		}elseif($nrReply > 0){
			$img = '../administrator/images/icon/p_reply.png';
		}else{
		        $img = '../administrator/images/icon/p_non.png';
		}

$i = 0;
while($objResult = mysql_fetch_array($objQuery)){
	$nrReply = mysql_num_rows(mysql_query("SELECT * FROM other_webboard_reply WHERE wbID = '".$objResult['wbID']."'"));
	$i++;
	$bg = ($i%2 = 0) ? "#e0eee0" : "";
	if((time()-86400) < $objResult['wbDate']){
	      $img = '../administrator/images/icon/p_new.png';
	}elseif($nrReply > 0){
		$img = '../administrator/images/icon/p_reply.png';
	}else{
	        $img = '../administrator/images/icon/p_non.png';
	}