<script type="text/javascript">
function plus(){
var num1=document.getElementById("text1").value;
var num2=document.getElementById("text2").value;
var result=parseInt(num1)+parseInt(num2);
document.getElementById("text3").value=result;
}
function reduce(){
var num1=document.getElementById("text1").value;
var num2=document.getElementById("text2").value;
var result=parseInt(num1)-parseInt(num2);
document.getElementById("text3").value=result;
}
function ride(){
var num1=document.getElementById("text1").value;
var num2=document.getElementById("text2").value;
var result=parseInt(num1)*parseInt(num2);
document.getElementById("text3").value=result;
}
function divide(){
var num1=document.getElementById("text1").value;
var num2=document.getElementById("text2").value;
var result=parseInt(num1)/parseInt(num2);
document.getElementById("text3").value=result;
}
function reset(){
document.getElementById("text1").value="";
document.getElementById("text2").value="";
document.getElementById("text3").value="";
}
function disptime()
{
var time = new Date( );
var hour = time.getHours( );
var minute = time.getMinutes( );
var second = time.getSeconds( );
if(hour<12){
if(second<10){
second="0"+second;
document.myform.myclock.value ="AM:"+hour+":"+minute+":"+second+" " ;
}
else{
document.myform.myclock.value ="AM:"+hour+":"+minute+":"+second+" " ;
}
}
else{
if(second<10){
second="0"+second;
document.myform.myclock.value ="PM:"+hour+":"+minute+":"+second+" " ;
}
else{
document.myform.myclock.value ="PM:"+hour+":"+minute+":"+second+" " ;
}
}
var myTime = setTimeout("disptime()",1000);
}
function openFirst(){
window.open("adv.html","广告窗口","toolbars=0,location=0,statusbars=0,menubars=0,width=500,height=500,scrollbars=1,top=200,left=600");
}
</script>
</head>
<body onload="openFirst()">
<form name="myform">
<table align="center">
<tr>
<td align="center" colspan="2" id="td1">
计算器
</td>
</tr>
<tr>
<td>输入第一个数字：</td>
<td><input type="text" name="Text1" id="text1"></td>
</tr>
<tr>
<td>输入第二个数字：</td>
<td><input type="text" name="Text2" id="text2"></td>
</tr>
<tr>
<td colspan="2" >
<span> </span><button onclick="plus()"><img src="图片/jia.jpg"></button><span> </span>
<span> </span><button onclick="reduce()"><img src="图片/jian.jpg"></button><span> </span>
<span> </span><button onclick="ride()"><img src="图片/cheng.jpg"></button><span> </span>
<span> </span><button onclick="divide()"><img src="图片/chu.jpg"></button><span> </span>
</td>
</tr>
<tr>
<td >结算结果：</td>
<td><input type="text" name="Txet3" id="text3"></td>
</tr>
<tr>
<td colspan="2" align="center">
<button value="btn" onclick="reset()"><strong>重置</strong></button>
</td>
</tr>
<tr>
<td colspan="2" align="center">
北京时间 <INPUT name="myclock" type="text" value="" size="10" id="text4" ><script type="text/javascript">disptime()</script>
</td>
</tr>
</table>
</form>
</body>
</html>
button按钮全部添加type="button"属性，要不默认是type="submit"提交按钮，提交表单了，
要么把form标签去掉
<tr>
<td colspan="2">
<span> </span><button type="button" onclick="plus()"><img src="图片/jia.jpg"></button><span> </span>
<span> </span><button type="button" onclick="reduce()"><img src="图片/jian.jpg"></button><span> </span>
<span> </span><button type="button" onclick="ride()"><img src="图片/cheng.jpg"></button><span> </span>
<span> </span><button type="button" onclick="divide()"><img src="图片/chu.jpg"></button><span> </span>
</td>
</tr>
<tr>
<td>结算结果：</td>
<td><input type="text" name="Txet3" id="text3"></td>
</tr>
<tr>
<td colspan="2" align="center">
<button value="btn" type="button" onclick="reset()"><strong>重置</strong></button>
</td>
</tr>
非常感谢！！！抱歉好久才看到······