셀렉트 박스 페이지 이동 시 값 유지 질문드립니다. 채택완료

</p>

<p><select name="sel" onchange="location.href=this.value">

        <option value="">과일</option>

        <option value="?bo_table=free&sca=&sop=and&sfl=wr_subject&stx=사과"<?php if($sel=="?bo_table=free&sca=&sop=and&sfl=wr_subject&stx=사과​"){echo"selected";}?>>사과</option>

        <option value="?bo_table=free&sca=&sop=and&sfl=wr_subject&stx=포도"<?php if($sel=="?bo_table=free&sca=&sop=and&sfl=wr_subject&stx=포도​"){echo"selected";}?>>포도</option>

        <option value="?bo_table=free&sca=&sop=and&sfl=wr_subject&stx=감"<?php if($sel=="?bo_table=free&sca=&sop=and&sfl=wr_subject&stx=감​"){echo"selected";}?>>감</option>

</select></p>

<p>