输入实时html

Question

我需要限制名称中的最大输入值=＆＃34; name＆＃34;领域。 实时处理。 <input max = 100>约束不起作用。 我怎么能这样做？

 <script>
        function showcost() {
            document.getElementById("cost").value = document.getElementById('serviceslist').value;
        }
        function sum2() {
            var x = document.getElementById('cost2').value;
            var y = document.getElementById('amount2').value;
            var total = (parseFloat(x) * parseFloat(y))/100;
            document.getElementById("total2").value = total;
        }
    </script>

    <br>
<div class="container">
    <div class="row">
        <div class="col-md-12 col-md-offset-0">

    <form>

        <p>Procent:<input name="name" size="3" min=1 max=100 type="number" id="amount2"  step=1 id="cost2" pattern="[0-9]" onchange="sum2()" oninput="this.value = this.value.replace(/[^0-9]/g, '').replace(/(\..*)\./g, '$1');" );" ></p>
        <p>Результат:<input type="text" id="total2" value="0" disabled></p>
    </form>
        </div>
    </div>
</div>