Php 保留从下拉框中选择的排名值

我正在对产品的价值进行排名，并在下拉菜单中列出它们。我似乎无法从下拉菜单中保留选定的排名值。任何帮助都将不胜感激，提前谢谢

<?php

$sessionid = $_SESSION['uid'];

$period = ".&nbsp";

$info = $conn->prepare("SELECT `productid`,`name` FROM `products` WHERE id = :id  ORDER     BY `name` DESC ");
$info ->bindParam(':id', $sessionid , PDO::PARAM_INT);
$info->execute();

$rank = 0;
$last_score = false;
$rows = 0;

$ops = '';  

while ($userinfo = $info->fetchobject()) {


$rows++;
if( $last_score!= $userinfo->name ){
$last_score = $userinfo->name;
$rank++;
}

$productid1 = "$userinfo->productid";
$name1 = "$userinfo->name";
$ops.= "<option value='" . $productid1 . "'>" . $rank . "" . $period . "" . $name1 .   "</option>";

}          
?>

<form action="store.php" method="POST">

<b>Select a product from our top ranking product list. </b> </br>
<select name= "products" >

<?php echo $ops ?> <?php if($_POST['products']=='$ops') echo "selected =  \"selected\""; ?>>
</select>
</br>
<input type="submit" name="Submit" value="Submit"/>
</form>

---

在您拥有它的地方，这将不起作用：

if($_POST['products']=='$ops') echo "selected =  \"selected\"";

您需要在此处执行此操作：

$ops .= "<option value='" . $productid1 . "'";
if($_POST['products']==$productid1) {$ops .= "selected =  'selected'";}
$ops .= ">" . $rank . "" . $period . "" . $name1 .   "</option>";

$ops.=''$等级"" . $时期"" . $名字1。"";
试试这个：

<?php

$sessionid = $_SESSION['uid'];

$period = ".&nbsp";

$info = $conn->prepare("SELECT `productid`,`name` FROM `products` WHERE id = :id  ORDER         BY `name` DESC ");
$info ->bindParam(':id', $sessionid , PDO::PARAM_INT);
$info->execute();

$rank = 0;
$last_score = false;
$rows = 0;

$ops = '';  

while ($userinfo = $info->fetchobject()) {


$rows++;
if( $last_score!= $userinfo->name ){
$last_score = $userinfo->name;
$rank++;
}

$productid1 = "$userinfo->productid";
$name1 = "$userinfo->name";
if($_POST['products']== $productid1){
   $sel = "selected = 'selected'";
}
$ops.= "<option value='" . $productid1 . "'". $sel . ">" . $rank . "" . $period . "" . $name1 .   "</option>";

}