risolto grazie
Emanuela

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<form method="get" action="">


Nominativo
<input name="radiobutton" type="radio" value="" onclick="this.form.rivenditore.disabled=true; this.form.agente.disabled=true">


Cantatto
<input name="radiobutton" type="radio" value="c" onclick="this.form.rivenditore.disabled=true; this.form.agente.disabled=true">


Cliente
<input name="radiobutton" type="radio" onclick="this.form.rivenditore.disabled=false; this.form.agente.disabled=false" value="d">
</p>



<select name="rivenditore" disabled>
<option>scegli il rivenditore</option>
<option>rivenditore1</option>
<option>rivenditore2</option>
</select>
</p>



<select name="agente" disabled>
<option>scegli il Agente</option>
<option>Agente1</option>
<option>Agente2</option>
</select>
</p>
</form>

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