<head>
<title>计算器</title>
</head>
<body bgcolor="#ffffff" onload="FKeyPad.ReadOut.focus()FKeyPad.ReadOut.select()">
<FORM name="Keypad" action="">
<TABLE align="center">
<B>
<TABLE align="center" border=2 width=50 height=60 cellpadding=1 cellspacing=5>
<TR>
<TD colspan=3 align=middle><input name="ReadOut" type="Text" onkeypress="CheckOut()" size=24 value="0"
width=100%></TD>
<TD></TD>
<TD><input name="btnClear" type="Button" value=" C " onclick="Clear()"></TD>
<TD><input name="btnClearEntry" type="Button" value=" CE " onclick="ClearEntry()"></TD>
</TR>
<TR>
<TD><input name="btnSeven" type="Button" value=" 7 " onclick="NumPressed(7)"></TD>
<TD><input name="btnEight" type="Button" value=" 8 " onclick="NumPressed(8)"></TD>
<TD><input name="btnNine" type="Button" value=" 9 " onclick="NumPressed(9)"></TD>
<TD></TD>
<TD><input name="btnNeg" type="Button" value=" +/- " onclick="Neg()"></TD>
<TD><input name="btnPercent" type="Button" value=" % " onclick="Percent()"></TD>
</TR>
<TR>
<TD><input name="btnFour" type="Button" value=" 4 " onclick="NumPressed(4)"></TD>
<TD><input name="btnFive" type="Button" value=" 5 " onclick="NumPressed(5)"></TD>
<TD><input name="btnSix" type="Button" value=" 6 " onclick="NumPressed(6)"></TD>
<TD></TD>
<TD align=middle><input name="btnPlus" type="Button" value=" + " onclick="Operation('+')"></TD>
<TD align=middle><input name="btnMinus" type="Button" value=" - " onclick="Operation('-')"></TD>
</TR>
<TR>
<TD><input name="btnOne" type="Button" value=" 1 " onclick="NumPressed(1)"></TD>
<TD><input name="btnTwo" type="Button" value=" 2 " onclick="NumPressed(2)"></TD>
<TD><input name="btnThree" type="Button" value=" 3 " onclick="NumPressed(3)"></TD>
<TD></TD>
<TD align=middle><input name="btnMultiply" type="Button" value=" * " onclick="Operation('*')"></TD>
<TD align=middle><input name="btnDivide" type="Button" value=" / " onclick="Operation('/')"></TD>
</TR>
<TR>
<TD><input name="btnZero" type="Button" value=" 0 " onclick="NumPressed(0)"></TD>
<TD><input name="btnDecimal" type="Button" value=" . " onclick="Decimal()"></TD>
<TD colspan=2></TD>
<TD><input name="btnEquals" type="Button" value=" = " onclick="Operation('=')"></TD>
<TD><input name="btnReturn" type="Button" value="返 回" onclick="goReturn()"></TD>
</TR>
</TABLE>
</TABLE>
</B>
</FORM>
</CENTER>
<font face="Verdana, Arial, Helvetica" size=2>
<SCRIPT LANGUAGE="JavaScript">
<!-- Begin
var FKeyPad = document.forms['Keypad']
var Accum = "0"
var FlagNewNum = false
var PendingOp = ""
//===============================================================================
//[描述] 浮点数精确计算
//[参数] str1 - 第一个数
// str2 - 第二个数
// type - 运算符
// precision - 小数位精度
//[调用方式] longCount(str1,str2,type,precision)
//[返回值] 计算结果
//===============================================================================
function longCount(str1,str2,type) {
var comma1 = 0
if (str1.indexOf(".")!=-1) {
str1 = str1.replace(/0*$/,"")
comma1 = str1.length - str1.indexOf(".")-1
}
var comma2 = 0
if (str2.indexOf(".")!=-1) {
str2 = str2.replace(/0*$/,"")
comma2 = str2.length - str2.indexOf(".")-1
}
str1 = str1.replace(/\./,"")
str2 = str2.replace(/\./,"")
var value,comma
if (type!="*") {
if (comma1>comma2) {
for (var i=0i<comma1-comma2i++) str2 += "0"
comma = (type=="/")?0:comma1
}else {
for (var i=0i<comma2-comma1i++) str1 += "0"
comma = (type=="/")?0:comma2
}
}else {
comma = comma1 + comma2
}
if (type=="+") {
value = parseInt(str1,10) + parseInt(str2,10)
}else if (type=="-") {
value = parseInt(str1,10) - parseInt(str2,10)
}else if (type=="*") {
value = parseInt(str1,10) * parseInt(str2,10)
}else if (type=="/") {
value = parseInt(str1,10) / parseInt(str2,10)
}
value = String(value)
if (comma>0) value = value.substring(0,value.length-comma)+"."+value.substring(value.length-
comma,value.length)
if (value.indexOf(".")!=-1)
value = value.replace(/0*$/,"")
return value
}
function NumPressed (Num) {
if (FlagNewNum) {
FKeyPad.ReadOut.value = Num
FlagNewNum = false
}
else {
if (FKeyPad.ReadOut.value == "0")
FKeyPad.ReadOut.value = Num
else
FKeyPad.ReadOut.value += Num
}
}
function Operation (Op) {
var Readout = FKeyPad.ReadOut.value
if (FlagNewNum &&PendingOp != "=")
else
{
FlagNewNum = true
if ( '+' == PendingOp || '-' == PendingOp || '/' == PendingOp || '*' == PendingOp)
Accum = longCount(Accum,Readout,PendingOp)
else
Accum = Readout
FKeyPad.ReadOut.value = Accum
PendingOp = Op
FKeyPad.ReadOut.focus()
FKeyPad.ReadOut.select()
}
}
function Decimal () {
var curReadOut = FKeyPad.ReadOut.value
if (FlagNewNum) {
curReadOut = "0."
FlagNewNum = false
}
else
{
if (curReadOut.indexOf(".") == -1)
curReadOut += "."
}
FKeyPad.ReadOut.value = curReadOut
}
function ClearEntry () {
FKeyPad.ReadOut.value = "0"
FlagNewNum = true
}
function Clear () {
Accum = "0"
PendingOp = ""
ClearEntry()
}
function Neg () {
alert(FKeyPad.ReadOut.value)
FKeyPad.ReadOut.value = longCount(FKeyPad.ReadOut.value,"-1","*")
}
function Percent () {
FKeyPad.ReadOut.value = longCount(FKeyPad.ReadOut.value,Accum,"*")
FKeyPad.ReadOut.value = longCount(FKeyPad.ReadOut.value,100,"/")
}
function goReturn() {
top.returnValue = FKeyPad.ReadOut.value
self.close()
}
function CheckOut() {
var keyCode = window.event.keyCode
if (keyCode>=48 &&keyCode<=57) {
if (FlagNewNum) {
FKeyPad.ReadOut.value = ""
//window.event.keyCode = null
FlagNewNum = false
}
return true
}else if (keyCode==43 || keyCode==45 || keyCode==42 || keyCode==47 || keyCode==61) {
Operation(String.fromCharCode(keyCode))
}else if (keyCode==46) {//.
if (FKeyPad.ReadOut.value.indexOf(".") == -1)
return true
}else if (keyCode==13) goReturn()
window.event.returnValue = false
return false
}
// End -->
</SCRIPT>
</body>
</html>
我这里有一个现成的，自己再改一下吧（<HTML><HEAD>
<SCRIPT LANGUAGE = "JavaScript">
function calcu(){
var numb1= document.calc.num1.value
var numb2= document.calc.num2.value
var total= parseFloat(numb1)*parseFloat(numb2)
document.calc.result.value=total
}
</SCRIPT>
<script type="text/javascript" language="JavaScript1.2" src="menu.js"></script>
</HEAD>
<BODY>
<FORM name="calc">
<P><BR>
<font size="5">会说话的QQ竞拍喽！</fo
<BR>
竟拍价?
<INPUT name="num2" TYPE="text" id="num2" value="120" size="15"><BR>
购买数量：
<INPUT TYPE="text" name="num1" size="15"> <BR>
预计总价：
<INPUT name="result" TYPE="text" size="15">
</P>
<P>
<INPUT name="getAnswer" TYPE="button" id="getAnswer" onClick="calcu()"
value="计算看看"><!--单机鼠标调
</P>
</FORM>
</BODY>
</HTML>
）
