Holas...!soy nuevo y tengo un gran problema, intento por varios lados y pudo guadar los chekbox seleccionados en mi campo zona_a, este es mi codigo:
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<td height="40" colspan="2" align="center" valign="middle" style="border:1px solid #CCCCCC"><strong class="texto">ZONAS TEMATICAS A RECORRER</strong></td>
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<td height="24" align="left" valign="middle" style="border:1px solid #CCCCCC"> A: Zona Costa:
<label></label></td>
<td valign="middle"><input type="checkbox" name="zona_a" id="zona_a" value="Zona Costa" onClick="zonas(this)"/></td>
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<td height="2"></td>
<td></td>
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<td height="24" align="left" valign="middle" style="border:1px solid #CCCCCC"> B: Zona Sierra:</td>
<td valign="middle"><input type="checkbox" name="zona_a" id="zona_a" value="Zona Sierra" onClick="zonas(this)"/></td>
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<td height="2"></td>
<td></td>
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<td height="24" valign="middle" style="border:1px solid #CCCCCC"> C: Zona Selva:</td>
<td valign="middle"><input type="checkbox" name="zona_a" id="zona_a" value="Zona Selva" onClick="zonas(this)"/></td>
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<td height="2"></td>
<td></td>
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<td height="24" valign="middle" style="border:1px solid #CCCCCC"> D: Zona Internacional</td>
<td valign="top"><input type="checkbox" name="zona_a" id="zona_a" value="Zona Internacional" onClick="zonas(this)"/></td>
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<td height="2"></td>
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<td height="24" valign="middle" style="border:1px solid #CCCCCC"> E: Zona Arqueológica</td>
<td valign="middle"><input type="checkbox" name="zona_a" id="zona_a" value="Zona Arqueologica" onClick="zonas(this)"/></td>
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<td height="2"></td>
<td></td>
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<td height="24" valign="middle" style="border:1px solid #CCCCCC"> F: Zona Jardin Botánico</td>
<td valign="middle"><input type="checkbox" name="zona_a" id="zona_a" value="Zona Jardin Botanico" onClick="zonas(this)"/></td>
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<td height="2"></td>
<td></td>
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<td rowspan="2" valign="middle" style="border:1px solid #CCCCCC"> G: Zona Cactario y Especies Nativas</td>
<td height="20" valign="middle"><input type="checkbox" name="zona_a" id="zona_a" value="Zona Cactario de Lima" onClick="zonas(this)"/></td>
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<td height="1"></td>
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