php如何使用echo输出常量+变量?

Question

//替换图片Alt为文档标题$this->Fields['body'] = str_ireplace(array('alt=""','alt=\'\''),'',$this->Fields['body']);$this->Fields['body'] = preg_replace("@ [\s]{0,}alt[\s]{0,}=[\"'\s]{0,}[\s\S]{0,}[\"'\s] @isU"," ",$this->Fields['body']);$this->Fields['body'] = str_ireplace("<img " ,"<img alt='".$this->Fields['title']."' ",$this->Fields['body']);echo '<script lanuage="javascript">';echo 'alert("？");'; //输出$this->Fields['body']echo '</script>';这里输出如何写？又比如说这个$body = str_ireplace(array('alt=""','alt=\'\''),'',$body); echo '<script lanuage="javascript">';echo 'alert("?");'; //输出$body,PHP中的连接符是什么？echo '</script>';