我自己学习编程，我在html / js / css中做计算器。我已经看过这段代码，但是我无法弄清楚javascript，我想要一点帮助，如果你能向我解释一下javascript，就像评论一样，如果它对你来说更容易，我会非常感激。< / p>
<!DOCTYPE html>
<html>
<head>
<title>Simple Calculator</title>
<meta name="viewport" content="width=device-width, initial-scale=1">
<style>
input[type="button"]{
background:-webkit-gradient( linear, left top, left bottom, color-stop(0.05, #606060), color-stop(1, #606060) );
background:-moz-linear-gradient( center top, #606060 5%, #606060 100% );
filter:progid:DXImageTransform.Microsoft.gradient(startColorstr='#606060', endColorstr='#606060');
background-color:#606060;
border:1px solid #606060;
display:inline-block;
color:#fff;
font-family:Arial;
font-size:50px;
line-height:28px;
text-decoration:none;
text-align:center;
margin-bottom:1.5px;
margin-left: 1.5px;
margin-right:1.5px ;
margin-top:1.5px ;
height: 75px;
}
input[type="button"]{
width: 184px;
}
#btnC{
width:372.7px;
}
#btn0{
width:374.7px;
}
#btn0,#btndecimal,#btndivide {
margin-right: 0.1px;
}
#btn7,#btn4,#btn1,#btn0,#btnequals {
margin-left: 0.01px;
}
#btnequals {
height: 61px;
width: 944px;
margin-top: 3px;
}
input[type="button"]:active {
position:relative;
background:#989898;
}
input:focus {
outline:0;
}
input[type="Text"] {
padding-left: 10px;
margin-bottom: 1.5px;
font-size: 100px;
background-color: #202020 ;n
height:195px;
width: 935px;
border:none;
color:white;
}
body {
background-color: #080808 ;
overflow: hidden;
}
#about {
font-size: 45px;
}
</style>
</head>
<body>
<FORM name="Keypad" action="">
<input name="ReadOut" id="output" type="Text" size=24 value="0" readonly>
<table>
<tr>
<td><input id="btn7" type="Button" value=" 7 " onclick="NumPressed(7)"></td>
<td><input id="btn8" type="Button" value=" 8 " onclick="NumPressed(8)"></td>
<td><input id="btn9" type="Button" value=" 9 " onclick="NumPressed(9)"></td>
<td colspan="2"><input id="btnC" type="Button" value=" C " onclick="Clear()"></td>
</tr>
<tr>
<td><input id="btn4" type="Button" value=" 4" onclick="NumPressed(4)"></td>
<td><input id="btn5" type="Button" value=" 5 "onclick="NumPressed(5)"></td>
<td><input id="btn6" type="Button" value=" 6 " onclick="NumPressed(6)"></td>
<td><input id="btnplusminus" type="Button" value=" +/- " onclick="Neg()"></td>
<td><input id="btnplus" type="Button" value=" + " onclick="Operation('+')"></td>
</tr>
<tr>
<td><input id="btn1" type="Button" value=" 1 " onclick="NumPressed(1)"></td>
<td><input id="btn2" type="Button" value=" 2 " onclick="NumPressed(2)"></td>
<td><input id="btn3" type="Button" value=" 3 " onclick="NumPressed(3)"></td>
<td><input id="btnmultiply" type="Button" value=" * " onclick="Operation('*')"></td>
<td><input id="btnminus" type="Button" value=" - " onclick="Operation('-')"></td>
</tr>
</table>
<input id="btn0" type="Button" value=" 0 " onclick="NumPressed(0)">
<input id="btndecimal" type="Button" value=" . " onclick="Decimal()">
<input id="btndivide" type="Button" value=" / " onclick="Operation('/')">
<input id="about" type="Button" value="About" onclick="myFunction()"></br>
<input id="btnequals" type="Button" value=" = " onclick="Operation('=')">
</FORM>
<script>
var FKeyPad = document.Keypad;
var Accumulate = 0;
var FlagNewNum = false;
var PendingOp = "";
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 )
Accumulate += parseFloat(Readout);
else if ( '-' == PendingOp )
Accumulate -= parseFloat(Readout);
else if ( '/' == PendingOp )
Accumulate /= parseFloat(Readout);
else if ( '*' == PendingOp )
Accumulate *= parseFloat(Readout);
else
Accumulate = parseFloat(Readout);
FKeyPad.ReadOut.value = Accumulate;
PendingOp = Op;
}
}
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 () {
Accumulate = 0;
PendingOp = "";
ClearEntry();
}
function Neg () {
FKeyPad.ReadOut.value = parseFloat(FKeyPad.ReadOut.value) * -1;
}
function Percent () {
FKeyPad.ReadOut.value = (parseFloat(FKeyPad.ReadOut.value) / 100) * parseFloat(Accumulate);
}
</script>
<script>
function myFunction() {
alert("TegTech 2014");
}
</script>
</body>
</html>
答案 0 :(得分：1)
我可以在这里回答你关于变量的澄清问题，但是将来你会得到更好的结果，要求更小，更具体的问题。如果一个问题太宽泛，很容易摆脱话题＆amp;这种格式很难回答。
4个变量看起来是：
FKeyPad：此变量包含对文档键盘的引用。这是您输入的来源。
Accumulate：此变量用于包含正在执行的任何计算的总和。添加程序后，此编号将添加到＆amp;当程序使用减法时，从中减去。
FlagNewNum：这是一个布尔值，表示在当前的操作完成后是否还有更多操作要执行。
PendingOp：包含要执行的下一个操作，例如，如果下一个操作是添加，则此变量将包含'+'。