(1)整数和一位小数
<input type="number" placeholder="请输入扣分" οnkeyup="value=value.replace(/^\D*(\d*(?:\.\d{0,1})?).*$/g, '$1')"/>
(2)整数和两位小数
<input type="number" placeholder="请输入扣分" οnkeyup="value=value.replace(/^\D*(\d*(?:\.\d{0,2})?).*$/g, '$1')"/>
(3)整数
<input type="number" placeholder="请输入分值" οninput="value=value.replace(/[^\d]/g,'')" maxlength="3" />