Hola
Prueba así
Código Javascript
:
Ver original<html>
<head>
<script type="text/javascript">
function cambiarTalle(val,txt) {
document.itemsform.text2.value = txt;
document.itemsform.text3.value = val;
if (val == 25) {
document.itemsform.agregar1.value = val*8;
}
}
function buyItem(newQuantity) {
alert(newQuantity);
}
</script>
</head>
<body>
<form NAME="itemsform" >
<input TYPE="text" NAME="agregar1" VALUE="1" SIZE="3">
<select size="1" name="newTalle" onChange="cambiarTalle(this.value,this.options[this.selectedIndex].innerHTML)" id="talleSelect">
<option value="26" selected>T1bb</option>
<option value="29">T12</option>
<option value="25">Curva</option>
</select>
<select size="1" name="newTalle2" onChange="cambiarTalle(this.value,this.options[this.selectedIndex].innerHTML)" id="talleSelect">
<option value="26" selected>T1bb</option>
<option value="29">T12</option>
<option value="25">Curva</option>
</select>
<input name="text2" type="text" style="border:0;" value="T1bb" size="2" >$
<input name="text3" type="text" style="border:0;" value="26" size="2">
<input name="cbtadd" type="button" value="Agregar" onClick="buyItem(document.itemsform.agregar1.value)" >
</form>
</body>
</html>
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