javascript验证表单字段有效性，使用checkValidity()方法和他的属性

 <script type="text/javascript">function LoginCheckValidity(){var txt="";var rmb1=document.getElementById("rmb1");if(rmb1.checkValidity()==false){if(rmb1.validitionMessage==undefined){txt="输入金额有误,金额10-200之间";}}else{txt="转账成功！";}document.getElementById("rmb1msg").innerHTML=txt;//setCustomValidity()为自定义信息var rmb2=document.getElementById("rmb2");rmb2.setCustomValidity("");if(rmb2.value==null || rmb2.value==""){rmb2.setCustomValidity("请输入金额！");}else if(rmb2.validity.rangeUnderflow){rmb2.setCustomValidity("金额不小于10元");}else if(rmb2.validity.rangeOverflow){rmb2.setCustomValidity("金额不大于200万");}else {rmb2.setCustomValidity("转账成功！");}document.getElementById("rmb2msg").innerHTML=rmb2.validationMessage;rmb2=null;rmb1=null;}var input=document.getElementsByName("submit1")[0];EventUtil.addHandler(input,"click",LoginCheckValidity);input=null;</script>

//html部分

<div style="width:500px"><div style="width:250px;height:30px;line-height:30px;float:left;background:green;text-align:right;">转账金额1：<input id="rmb1" type="number"  min="10" max="200" name="rmb1" required="" size="20"/></div><div style="width:250px;height:30px;line-height:1px;float:left;background:black;color:red;"><p id="rmb1msg"></p></div></div><div style="clear:both;"></div><div style="width:500px;margin-top:10px;"><div style="width:250px;height:30px;line-height:30px;float:left;background:green;text-align:right;">转账金额2：<input id="rmb2" type="number"  min="10" max="200" name="rmb2" required="" size="20"/></div><div style="width:250px;height:30px;line-height:1px;float:left;background:black;color:red;"><p id="rmb2msg"></p></div></div><div style="clear:both;"></div><div style="float:left;margin-top:10px;"><input type="submit" name="submit1" value="验证" /></div>