<form class="layui-form" method="post" id="myForm">
    <div class="layui-form-item layui-layout-admin">
        <div class="layui-input-block">
            <button type="submit" class="layui-btn btn-block">提交</button>
        </div>
    </div>
</form>

<script>
layui.use(['form','layer','jquery'], function(){
    var form = layui.form;
    var layer = layui.layer;
    var $ = layui.jquery;

    // 拦截表单提交
    $('#myForm').on('submit', function(e){
        e.preventDefault(); // 阻止默认提交

        layer.confirm('请确认选择是否正确？', {icon: 3, title:'确认提交'}, function(index){
            // 用户点击“确定”后提交表单
            e.target.submit(); // 或者 $(e.target).off('submit').submit(); 防止死循环
            layer.close(index);
        });
    });
});
</script>