正则表达式

只能输入纯数字

onkeyup="this.value=this.value.replace(/\D/g,'')"; 
onafterpaste="this.value=this.value.replace(/\D/g,'')";

只能输入中文

　onkeyup="value=value.replace(/[^\u4E00-\u9FA5]/g,'')" ；onbeforepaste="clipboardData.setData('text',clipboardData.getData('text').replace(/[^\u4E00-\u9FA5]/g,''))"

开头不能为0，不能有小数点 

onkeyup="this.value=this.value.replace(/\D|^0/g,'')" onafterpaste="this.value=this.value.replace(/\D|^0/g,'')"

开头不能为0

<div class="input-choseNum">

<input type="number" id="inp-chooseNum" oninput='this.value=this.value.replace(/^[0]+[0-9]*$/gi,"")' maxlength="5" />

<span class="sureChoose">确定</span><span class="closeChoose">取消</span>

</div>