<?php
# valor de conversión
if(isset($_POST["conversion"]) && (is_numeric($_POST["conversion"]) || is_numeric(str_replace(",",".",$_POST["conversion"]))))
{
$conversion=str_replace(",",".",$_POST["conversion"]);
}else{
$conversion=813558.89;
}
# valor a convertir
if(isset($_POST["aconvertir"]) && (is_numeric($_POST["aconvertir"]) || is_numeric(str_replace(",",".",$_POST["aconvertir"]))))
{
$aconvertir=str_replace(",",".",$_POST["aconvertir"]);
}else{
$aconvertir=0;
}
# calculo
$resultado=$conversion*$aconvertir;
?>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<meta http-equiv="Content-Type" content="text/html; charset=gb18030">
<title>Cambio Bol��vares a Real</title>
<style>
centrado-porcentual {
position: absolute;
left: 50%;
top: 50%;
transform: translate(-50%, -50%);
-webkit-transform: translate(-50%, -50%);
}
form span {
display:block;
float:left;
width:160px;
}
input {text-align:right;}
</style>
</head>
<body>
<div class="centrado-porcentual">
<h1>Real en Bolívares Fuertes</h1>
<form action="<?php echo $_SERVER["PHP_SELF"]?>" method="post">
<span>Valor del Real</span>
<input type="text" name="conversion" value="<?php echo $conversion?>">
<br><span>Real R$</span>
<input type="text" name="aconvertir" value="<?php echo $aconvertir?>">
<br><span>Bolivares</span>
<input type="text" name="resultado" readonly value="<?php echo number_format($resultado,2,".",",")?>">
<p><input type="submit" value="Calcular"></p>
</form>
</div>
</body>
</html>