Criei uma calculadora em JavaScript e CSS, esou divulgando aki p auxiliar no material de estudos e tb para comentários q saum tds bem vindos, inclusive críticas.
Abçs a Tds
<html><head><title>Calculadora</title></head><body>
<script type="text/javascript">
<!--
var Accum = 0;
var FlagNewNum = false;
var PendingOp = "";
//Abaixo estamos adcionando os valores de cada botão ao parametro Num
function NumPressed(Num) {
if (FlagNewNum) {
document.frm_calc.txt_01.value = Num;
FlagNewNum = false;
}
else {
if (document.frm_calc.txt_01.value == "0")
document.frm_calc.txt_01.value = Num;
else
document.frm_calc.txt_01.value += Num;
}
}
//Valores de exibição quando apertado o botão igual
function Operation(Op) {
if (document.frm_calc.txt_01.value == ""){
alert("O Campo esta vázio digite um valor");
document.frm_calc.txt_01.value ="0"; }
else{
if (FlagNewNum && PendingOp != "=");
else {
FlagNewNum = true;
if ( '+' == PendingOp )
Accum += parseFloat(document.frm_calc.txt_01.value);
else if ( '-' == PendingOp )
Accum -= parseFloat(document.frm_calc.txt_01.value);
else if ( '/' == PendingOp )
Accum /= parseFloat(document.frm_calc.txt_01.value);
else if ( '*' == PendingOp )
Accum *= parseFloat(document.frm_calc.txt_01.value);
else
Accum = parseFloat(document.frm_calc.txt_01.value);
document.frm_calc.txt_01.value = Accum;
PendingOp = Op;
}
}
}
//Atribuindo o ponto( . ) aos valores numéricos
function Ponto() {
var curtxt_01 = document.frm_calc.txt_01.value;
if (FlagNewNum) {
curtxt_01 = "0.";
FlagNewNum = false;
}
else {
if (curtxt_01.indexOf(".") == -1)
curtxt_01 += ".";
}
document.frm_calc.txt_01.value = curtxt_01;
}
-->
</script>
<form name="frm_calc" acton>
<center>
<table width="200" cellpadding="3" cellspacing="5" style="color:#FFB90F; background-color:#000000; border:2pt solid#FFB90F">
<tr>
<td colspan="5"align="Center" bgColor="#FFB90F"><Font Face="Verdana" Size="4" Color="#000000"><b>Calculadora</b></font></td>
</tr>
<tr>
<td colspan="3" align="center" border:2pt solid#FFB90F><input type="text" name="txt_01" value="0" style="color:#000000; background-color:#CFCFCF;border:2pt solid#FFB90F"></td>
<td><center><input type="reset" value="AC" onclick="" style="color:#FFB90F; background-color:#000000; cursor:hand; padding:9px; border:0"></center></td>
<td><center><input type="button" value="=" name="btn_igual" onclick="Operation('=')" style="color:#FFB90F; background-color:#000000; cursor:hand; padding:9px; border:0"></center></td>
</tr>
<tr>
<td><center><input type="button" value="7" name="btn_7" onclick="NumPressed(7)" style="color:#FFB90F; background-color:#000000; cursor:hand; padding:9px; border:0"></center></td>
<td><center><input type="button" value="8" name="btn_8" onclick="NumPressed(8)" style="color:#FFB90F; background-color:#000000; cursor:hand; padding:9px; border:0"></center></td>
<td><center><input type="button" value="9" name="btn_9" onclick="NumPressed(9)" style="color:#FFB90F; background-color:#000000; cursor:hand; padding:9px; border:0"></center></td>
<td><center><input type="button" value="+" name="btn_soma" onclick="Operation('+')" style="color:#FFB90F; background-color:#000000; cursor:hand; padding:9px; border:0"></center></td>
<td><center><input type="button" value="-" name="btn_subt" onclick="Operation('-')" style="color:#FFB90F; background-color:#000000; cursor:hand; padding:9px; border:0"></center></td>
</tr>
<tr>
<td><center><input type="button" value="4" name="btn_4" onclick="NumPressed(4)" style="color:#FFB90F; background-color:#000000; cursor:hand; padding:9px; border:0"></center></td>
<td><center><input type="button" value="5" name="btn_5" onclick="NumPressed(5)" style="color:#FFB90F; background-color:#000000; cursor:hand; padding:9px; border:0"></center></td>
<td><center><input type="button" value="6" name="btn_6" onclick="NumPressed(6)" style="color:#FFB90F; background-color:#000000; cursor:hand; padding:9px; border:0"></center></td>
<td><center><input type="button" value="*" name="btn_mult" onclick="Operation('*')" style="color:#FFB90F; background-color:#000000; cursor:hand; padding:9px; border:0"></center></td>
<td><center><input type="button" value="/" name="btn_divi" onclick="Operation('/')" style="color:#FFB90F; background-color:#000000; cursor:hand; padding:9px; border:0"></center></td>
</tr>
<tr>
<td><center><input type="button" value="1" name="btn_1" onclick="NumPressed(1)" style="color:#FFB90F; background-color:#000000; cursor:hand; padding:9px; border:0"></center></td>
<td><center><input type="button" value="2" name="btn_2" onclick="NumPressed(2)" style="color:#FFB90F; background-color:#000000; cursor:hand; padding:9px; border:0"></center></td>
<td><center><input type="button" value="3" name="btn_3" onclick="NumPressed(3)" style="color:#FFB90F; background-color:#000000; cursor:hand; padding:9px; border:0"></center></td>
<td><center><input type="button" value="0" name="btn_0" onclick="NumPressed(0)" style="color:#FFB90F; background-color:#000000; cursor:hand; padding:9px; border:0"></center></td>
<td><center><input type="button" value="." name="btn_pont" onclick="Ponto()" style="color:#FFB90F; background-color:#000000; cursor:hand; padding:9px; border:0"></center></td>
</tr>
</table>
</form></center>
</body>
</html>
