从 JSONarray 获取值

Question

我正在编写一个 PHP 脚本连接到数据库获取数组中的所有订单。（$结果）我想遍历数组并获取所有“userName”问题是，通过下面的代码，我只能获取数组中每个“userName”的第一个字符。我想要一个包含所有“userName”的数组。<?php$dbhost = 'localhost';$dbuser = 'user';$dbpass = 'password';$dbname = 'dbname';//Create database connection$dblink = new mysqli($dbhost, $dbuser, $dbpass, $dbname);$sql = "select * from ordertest";$retval = mysqli_query($dblink, $sql) or die(mysqli_error($dblink));$result = mysqli_fetch_array($retval, MYSQLI_ASSOC);if (mysqli_num_rows($retval) > 0) {    $arr = json_decode($result, true);    foreach ($result as $key => $value) {        echo $value["userName"];    }} else {    echo $sql;}

Answer 1

解决方案应该是：

<?php

    $sql = "select * from ordertest";

    // retrieve query result from DB

    $retval = mysqli_query($dblink, $sql) or die(mysqli_error($dblink));

    

    // if result not empty

    if (mysqli_num_rows($retval) > 0) {

        // retrieve single row from $retval

        while ($result = mysqli_fetch_array($retval, MYSQLI_ASSOC)) {

            echo $result["userName"];

            echo "\n";

        }

    } else {

        echo $sql;

    }