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<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <title>Insert title here</title>
</head>
<body>
    <form th:action="@{/}" method="post" th:object="${sampleListInput}">
        <div th:each="sampleInput : ${sampleListInput.sampleList}">
            <input type="checkbox" th:field="*{sampleList[__${sampleInputStat.index}__].checkbox}" th:checked="${sampleInput.checkbox}" />
            <!-- You can access other properties of sampleInput as needed -->
            <input type="text" th:field="*{sampleList[__${sampleInputStat.index}__].userName}" th:value="${sampleInput.userName}" />
        </div>
        <input type="submit">
    </form>
</body>