我在php中有一段代码，我想把它放在循环中，“It is in switch case”，但我不知道怎么做。这真的让我有一个更短的代码。当然，在其他的switch case中，我有更多这样的代码，我可以用你的模式来有一个简短的代码。
有人能帮我吗？

//Preview is the name of the button.
// The reason which I put the switch code is that when ever I take each the numbers it gives me that the column numbers.

(isset($_POST['Preview'])) {
//Prepare and bind

// Create connection
$conn = new mysqli($servername, $username, $password, $dbname);

// Check connection
if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
    exit;
}
// set parameters and execute
$DataArr = array();
$previewid = "1";
$clientshowid = "0";
$statusid = "0";
$country = $_POST['Sel_Country'];
$commodity = $_POST['Sel_Commodity'];
$no_col = $_POST['no_col'];
$start1 = $_POST['start1'];
$end1 = $_POST['end1'];
$DataArr[]="('$start1','$end1')";

switch ($no_col) {
    case '1':
        $stmt = $conn->prepare("INSERT INTO t3 (previewid, clientshowid, statusid,country,commodity,no_col,start1,end1) VALUES (?,?,?,?,?,?,?,?)");
        $stmt->bind_param("ssssssss", $previewid, $clientshowid, $statusid, $country, $commodity, $no_col, $start1, $end1);
        break;
    case '2':
        $start2 = $_POST['start2'];
        $end2 = $_POST['end2'];
        $stmt = $conn->prepare("INSERT INTO t3 (previewid, clientshowid, statusid,country,commodity,no_col,start1,end1,start2,end2) VALUES (?,?,?,?,?,?,?,?,?,?)");
        $stmt->bind_param("ssssssssss", $previewid, $clientshowid, $statusid, $country, $commodity, $no_col, $start1, $end1, $start2, $end2);
        $DataArr[]="('$start1','$end1','$start2','$end2')";