带有数组替换json输出的php while循环

我的php代码如下

<?php

require_once(dirname(__FILE__).'/connectionInfoTestNew.php');


$connectionInfo = new ConnectionInfo();
$connectionInfo->GetConnection();

if (!$connectionInfo->conn)
{
    //Connection failed
    echo 'No Connection';
}

else
{

    $query = 'select DISTINCT i.tabledetailid as tabledetailid, i.name as name, c.tabledetailid as tableDet from tabledetail i left join temporderdetail c on i.tabledetailid = c.tabledetailid';

    $stmt = sqlsrv_query($connectionInfo->conn, $query);

    if (!$stmt)
    {
        //Query failed
        echo 'Query failed';
    }

    else
    {
        $contacts = array(); //Create an array to hold all of the contacts

        while ($row = sqlsrv_fetch_array($stmt,SQLSRV_FETCH_ASSOC)) //While there are still contacts
        {               
            //the names must match exactly the property names in the contact class in our C# code.
            $contact= array("ID" => $row['tabledetailid'],
                             "Name" => $row['name'],
                             "tableDet" => $row['tableDet']);

            //Add the contact to the contacts array
            array_push($contacts, $contact);
        }

        //Echo out the contacts array in JSON format
        header('Content-type: application/json');
        $output = ['TableInfo' => $contacts];
        echo json_encode($output, JSON_PRETTY_PRINT);
    }
}?>

我的期望是替换tableDet:2和tableDet:3等。。。。。如tableDet所示：已占用示例，期望输出如下

{
"TableInfo": [
    {
        "ID": "1",
        "Name": "TABLE 01",
        "tableDet": "occupied"
    },
    {
        "ID": "2",
        "Name": "TABLE 02",
        "tableDet": "occupied"
    },
    {
        "ID": "3",
        "Name": "TABLE 03",
        "tableDet": null
    },
    {
        "ID": "4",
        "Name": "TABLE 04",
        "tableDet": null
    },
    {
        "ID": "5",
        "Name": "TABLE 05",
        "tableDet": "occupied"
    }]}

---

那么，我应该如何将数字输出1、2、3等替换为php代码中的字符串OutputOccuped，提前感谢您的支持

在循环中尝试以下内容：

if(isset($row['tableDet'])){// or !is_null() or is_numeric()
$tableDet = "occupied"; 
}else{
$tableDet = $row['tableDet']);//or = "free" or null
}
$contact= array(
     "ID" => $row['tabledetailid'],
      "Name" => $row['name'],
      "tableDet" => $tableDet);

---

将tableDet=>$row['tableDet']替换为tableDet=>isset$row['tableDet']？'占用：空。非常感谢。它工作得很好。很好。也许我应该解释一下…？：。。。叫做三元运算符，看：谢谢链接，真的很有帮助

if(isset($row['tableDet'])){// or !is_null() or is_numeric()
$tableDet = "occupied"; 
}else{
$tableDet = $row['tableDet']);//or = "free" or null
}
$contact= array(
     "ID" => $row['tabledetailid'],
      "Name" => $row['name'],
      "tableDet" => $tableDet);