<input type="number" name="score" id="score" oninput="checkNum(this.value,this.id，10)" class="layui-input" placeholder="请添加分值" >

JavaScript：

function checkNum(val,id,numLength) {
document.getElementById(id).value = val >= 0 ? val : 0;
if(val.length>numLength){
document.getElementById(id).value="";
document.getElementById(id).readOnly=true;
qxMsg("数值已超过最大值",function(){
document.getElementById(id).readOnly=false;
});