将PHP变量从HTML传递给Javascript

<script>
    var phpVariable = <?php echo $phpVariable; ?>;
    // 使用phpVariable进行后续的JavaScript操作
</script>

<div id="myDiv" data-php-variable="<?php echo $phpVariable; ?>"></div>

<script>
    var phpVariable = document.getElementById("myDiv").getAttribute("data-php-variable");
    // 使用phpVariable进行后续的JavaScript操作
</script>

<!-- HTML部分 -->
<button onclick="getPhpVariable()">获取PHP变量</button>

<script>
    function getPhpVariable() {
        var xhr = new XMLHttpRequest();
        xhr.onreadystatechange = function() {
            if (xhr.readyState === 4 && xhr.status === 200) {
                var phpVariable = xhr.responseText;
                // 使用phpVariable进行后续的JavaScript操作
            }
        };
        xhr.open("GET", "get_php_variable.php", true);
        xhr.send();
    }
</script>

// get_php_variable.php
<?php
    $phpVariable = "Hello, World!";
    echo $phpVariable;
?>