JQ 輸入框控制輸入 - 鍵盤上事件

<li style="width: 480px">限購數量&nbsp;&nbsp;<input type="number" name="limitNumber" min="0" value="<c:if test="${entityGood.limitNumber != -1}">${entityGood.limitNumber}</c:if><c:if test="${entityGood.limitNumber ==-1}"></c:if>" onkeyup="if(this.value.length==1){this.value=this.value.replace(/[^0-9]/g,'')}else{this.value=this.value.replace(/[^0-9]/g,'')}" onafterpaste="if(this.value.length==1){this.value=this.value.replace(/[^0-9]/g,'')}else{this.value=this.value.replace(/[^0-9]/g,'')}"/>
    (不填不限購 為0僅展示)
</li>