ok, ya lo hice y me dices si te sirve asi:
Código PHP:
<script language="javascript">
function validar_checkbox(f, obj) {
f = eval("document." + f);
obj = eval("f." + obj);
var total = obj.length;
var selected = false;
if (total != null) {
for (i=0; i<total; i++) {
if (obj[i].checked == true) {
obj[i].checked = false;
} else {
obj[i].checked = true;
}
}
} else {
if (obj.checked == true) {
obj.checked = false;
} else {
obj.checked = true;
}
}
}
</script>
Código HTML:
<form name="form1" method="post">
<input type="checkbox" name="mycheckbox" value="1"><br>
<input type="checkbox" name="mycheckbox" value="1"><br>
<input type="checkbox" name="mycheckbox" value="1"><br>
<input type="checkbox" name="mycheckbox" value="1"><br>
<input type="checkbox" name="mycheckbox" value="1"><br><br>
<input type="checkbox" name="seltotods1" value="1" onClick="validar_checkbox('form1', 'mycheckbox')">Seleccionar Todos
</form>
<form name="form2" method="post">
<input type="checkbox" name="mycheckbox" value="1"><br>
<input type="checkbox" name="mycheckbox" value="1"><br>
<input type="checkbox" name="mycheckbox" value="1"><br>
<input type="checkbox" name="mycheckbox" value="1"><br>
<input type="checkbox" name="mycheckbox" value="1"><br><br>
<input type="checkbox" name="seltotods1" value="1" onClick="validar_checkbox('form2', 'mycheckbox')">Seleccionar Todos
</form> saludos
