При делении на ноль результат выдает "Infinity". Как сделать так, чтобы вместо Infinity, в окошке писалось "На ноль делить нельзя!", либо выскакивал alert с данным сообщением? Вот код калькулятора:
<script>
var Fcalc = document.calc;
var Currents = 0;
var FlagNewNum = false;
var PendingOp = "";
function NumPressed (Num)
{
if (FlagNewNum)
{
Fcalc.Result.value = Num;
FlagNewNum = false;
}
else
{
if (Fcalc.Result.value == "0")
Fcalc.Result.value = Num;
else
Fcalc.Result.value += Num;
}
}
function Operation (Op)
{
var Result = Fcalc.Result.value;
if (FlagNewNum && PendingOp != "=")
{
Fcalc.Result.value = Currents;
}
else
{
FlagNewNum = true;
if ( '+' == PendingOp )
Currents += parseFloat(Result);
else if ( '-' == PendingOp )
Currents -= parseFloat(Result);
else if ( '/' == PendingOp )
Currents /= parseFloat(Result);
else if ( '*' == PendingOp )
Currents *= parseFloat(Result);
else
Currents = parseFloat(Result);
Fcalc.Result.value = Currents;
PendingOp = Op;
}
}
function Point ()
{
var curResult = Fcalc.Result.value;
if (FlagNewNum)
{
curResult = "0.";
FlagNewNum = false;
}
else
{
if (curResult.indexOf(".") == -1)
curResult += ".";
}
Fcalc.Result.value = curResult;
}
function Clear ()
{
Fcalc.Result.value = "0";
FlagNewNum = true;
}
function Neg ()
{
Fcalc.Result.value =
parseFloat(Fcalc.Result.value) * -1;
}
</script>
<form name="calc" class="calculator-form" action="">
<table class="calculator">
<tr>
<td colspan="5">
<input class="res-window" name="Result" style="height: 25px;" type="text" size="39" value="0">
</td>
</tr>
<tr>
<td><input class="little-button" type="button" value="7" onclick="NumPressed(7)"/></td>
<td><input class="little-button" type="button" value="8" onclick="NumPressed(8)"/></td>
<td><input class="little-button" type="button" value="9" onclick="NumPressed(9)"/></td>
<td><input class="little-button" type="button" value="/" onclick="Operation('/')"/></td>
<td><input class="little-button" type="button" value="C" onclick="Clear()"/></td>
</tr>
<tr>
<td><input class="little-button" type="button" value="4" onclick="NumPressed(4)"/></td>
<td><input class="little-button" type="button" value="5" onclick="NumPressed(5)"/></td>
<td><input class="little-button" type="button" value="6" onclick="NumPressed(6)"/></td>
<td><input class="little-button" type="button" value="*" onclick="Operation('*')"/></td>
<td><input class="little-button" type="button" value="±" onclick="Neg()"/></td>
</tr>
<tr>
<td><input class="little-button" type="button" value="1" onclick="NumPressed(1)"/></td>
<td><input class="little-button" type="button" value="2" onclick="NumPressed(2)"/></td>
<td><input class="little-button" type="button" value="3" onclick="NumPressed(3)"/></td>
<td><input class="little-button" type="button" value="-" onclick="Operation('-')"/></td>
<td rowspan="2"><input class="res-button" type="button" value="=" onclick="Operation('=')"/></td>
</tr>
<tr>
<td colspan="2"><input class="zero-button" type="button" value="0" onclick="NumPressed(0)"/></td>
<td><input class="little-button" type="button" value="." onclick="Point()"/></td>
<td><input class="little-button" type="button" value="+" onclick="Operation('+')"/></td>
</tr>
</table>
</form>