有趣的验证JS只能输入正整数

<html>
<head>
<title>只能输入正整数</title>
</head>
<body>
兑换数量：<input type="text" ID="txtNumber" Width="50px" onkeyup="if(this.value.length==1){this.value=this.value.replace(/[^1-9]/g,'')}else{this.value=this.value.replace(/\D/g,'')}"
                                    onafterpaste="if(this.value.length==1){this.value=this.value.replace(/[^1-9]/g,'0')}else{this.value=this.value.replace(/\D/g,'')}" />
<input type="button" ID="btn1" value=" 兑  换 " OnClick='return confirm("确定兑换？");' />
</body>
</html>

2021-06-29
2022-03-02
2022-12-23
2022-12-23
2021-06-08
2021-08-21
2022-12-23
2022-12-23