function valida_correo(email)
{
    var splitted = email.match("^(.+)@(.+)$");
    if(splitted == null) return false;
    if(splitted[1] != null )
    {
      var regexp_user=/^\"?[\w-_\.]*\"?$/;
      if(splitted[1].match(regexp_user) == null) return false;
    }
    if(splitted[2] != null)
    {
      var regexp_domain=/^[\w-\.]*\.[A-Za-z]{2,4}$/;
      if(splitted[2].match(regexp_domain) == null) 
      {
	    var regexp_ip =/^\[\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}\]$/;
	    if(splitted[2].match(regexp_ip) == null) return false;
      }
      return true;
    }
return false;
}
function valida_datos(strValidateStr,objValue,strError) 
{ 
    var epos = strValidateStr.search("="); 
    var  command  = ""; 
    var  cmdvalue = ""; 
    if(epos >= 0) 
    { 
     command  = strValidateStr.substring(0,epos); 
     cmdvalue = strValidateStr.substr(epos+1); 
    } 
    else 
    { 
     command = strValidateStr; 
    } 
    switch(command) 
    { 
        case "req": 
        case "required": 
         { 
           if(eval(objValue.value.length) == 0) 
           { 
              if(!strError || strError.length ==0) 
              { 
                strError = objValue.name + " : Campo requerido."; 
              }
              jAlert(strError, "Formulario de contacto") 
              return false; 
           }
           break;             
         }
        case "maxlength": 
        case "maxlen": 
          { 
             if(eval(objValue.value.length) >  eval(cmdvalue)) 
             { 
               if(!strError || strError.length ==0) 
               { 
                 strError = objValue.name + " : "+cmdvalue+" caracteres maximos."; 
               } 
               jAlert(strError, "Formulario de contacto")
               return false; 
             }
             break; 
          } 
        case "minlength": 
        case "minlen": 
           { 
             if(eval(objValue.value.length) <  eval(cmdvalue)) 
             { 
               if(!strError || strError.length ==0) 
               { 
                 strError = objValue.name + " : " + cmdvalue + " caracteres minimos  "; 
               }            
               jAlert(strError, "Formulario de contacto")
               return false;                 
             }
             break; 
            } 
        case "alnum": 
        case "alphanumeric": 
           { 
              var charpos = objValue.value.search("[^A-Za-z0-9]"); 
              if(objValue.value.length > 0 &&  charpos >= 0) 
              { 
               if(!strError || strError.length ==0) 
                { 
                  strError = objValue.name+": Solo estan permitidos caracteres alfanumericos."; 
                }//if 
                jAlert(strError, "Formulario de contacto")
                return false; 
              }//if 
              break; 
           }//case alphanumeric 
        case "num": 
        case "numeric": 
           { 
              var charpos = objValue.value.search("[^0-9]"); 
              if(objValue.value.length > 0 &&  charpos >= 0) 
              { 
                if(!strError || strError.length ==0) 
                { 
                  strError = objValue.name+": Solo estan permitidos caracteres numericos."; 
                }//if               
                jAlert(strError, "Formulario de contacto") 
                return false; 
              }//if 
              break;               
           }//numeric 
        case "alphabetic": 
        case "alpha": 
           { 
              var charpos = objValue.value.search("[^A-Za-z]"); 
              if(objValue.value.length > 0 &&  charpos >= 0) 
              { 
                  if(!strError || strError.length ==0) 
                { 
                  strError = objValue.name+": Solo estan permitidos caracteres numericos"; 
                }//if                             
                jAlert(strError, "Formulario de contacto")
                return false; 
              }//if 
              break; 
           }//alpha 
        case "email": 
          { 
               if(!valida_correo(objValue.value)) 
               { 
                 if(!strError || strError.length ==0) 
                 { 
                    strError = objValue.name+": Introduce una cuenta de correo valida."; 
                 }//if                                               
                 jAlert(strError, "Formulario de contacto") 
                 return false; 
               }//if 
           break; 
          }//case email 
        case "lt": 
        case "lessthan": 
         { 
            if(isNaN(objValue.value)) 
            { 
              jAlert(objValue.name+": Debe ser un numero."); 
              return false; 
            }//if 
            if(eval(objValue.value) >=  eval(cmdvalue)) 
            { 
              if(!strError || strError.length ==0) 
              { 
                strError = objValue.name + " : Debe ser menor que "+ cmdvalue; 
              }//if               
              jAlert(strError, "Formulario de contacto")
              return false;                 
             }//if             
            break; 
         }
        case "gt": 
        case "greaterthan": 
         { 
            if(isNaN(objValue.value)) 
            { 
              alert(objValue.name+": Debe ser un numero."); 
              return false; 
            }
             if(eval(objValue.value) <=  eval(cmdvalue)) 
             { 
               if(!strError || strError.length ==0) 
               { 
                 strError = objValue.name + " : Debe ser mayor que "+ cmdvalue; 
               }             
               jAlert(strError, "Formulario de contacto") 
               return false;                 
             }          
            break; 
         }
        case "regexp": 
         { 
            if(!objValue.value.match(cmdvalue)) 
            { 
              if(!strError || strError.length ==0) 
              { 
                strError = objValue.name+": Caracter unvalido encontrado"; 
              }                                                              
              jAlert(strError, "Formulario de contacto") 
              return false;                   
            }
           break; 
         }
        case "dontselect": 
         { 
            if(objValue.selectedIndex == null) 
            { 
              alert("Error en sintaxis."); 
              return false; 
            } 
            if(objValue.selectedIndex == eval(cmdvalue)) 
            { 
             if(!strError || strError.length ==0) 
              { 
              strError = objValue.name+": Por favor seleccione una opción."; 
              }//if                                                               
              jAlert(strError, "Formulario de contacto") 
              return false;                                   
             } 
             break; 
         }
		 case "checked": 
         { 
            if(objValue.checked == null) 
            { 
              alert("Error en sintaxis."); 
              return false; 
            } 
            if(objValue.checked == false) 
            { 
             if(!strError || strError.length ==0) 
              { 
              strError = objValue.name+": Debe aceptar para continuar."; 
              }                                                             
              jAlert(strError, "Formulario de contacto") 
              return false;                                   
             } 
             break; 
         }
    }
    return true; 
} 
function validacion(objFrm,arrObjDesc) 
{ 
 for(var itrobj=0; itrobj < arrObjDesc.length; itrobj++) 
 { 
   if(objFrm.elements.length <= itrobj) 
   { 
        alert("Error en sintaxis."); 
        return false; 
   }
   for(var itrdesc=0; itrdesc < arrObjDesc[itrobj].length ;itrdesc++) 
   { 
      if(valida_datos(arrObjDesc[itrobj][itrdesc][0], 
                 objFrm[itrobj],arrObjDesc[itrobj][itrdesc][1]) == false) 
       { 
	     objFrm[itrobj].focus();
         return false; 
       }
   }
 } 
}