Js php多项选择删除

<?php
if("确认删除"){
 
$num=$_POST['checkbox'];
 
foreach($num as $v){
    
        $sql="delete from aa where id =".$v;
        $aa=mysql_query($sql);
        echo "<script language='javascript'>location.href='www.baidu.com';</script>";
    }
}
?>

<input type='checkbox' name='checkbox[]' value='值'>
<input type='button' value='全选' onClick="this.value=check('checkbox[]')">
<script>
var checkflag = "false";
function check(fieldName) {
    var field=document.getElementsByName(fieldName);
    if (checkflag == "false") {
        for (i = 0; i < field.length; i++) {
        field[i].checked = true;
    }
    checkflag = "true";
    return "全选";
 
}else {
    for (i = 0; i < field.length; i++) {
        field[i].checked = false; }
        checkflag = "false";
        return "全选";
    }
}
</script>