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<input type="radio" name="geschlecht" value="m" <? if($geschlecht == 'm') { echo 'selected="selected"'; } ?>> m
<input type="radio" name="geschlecht" value="w" <? if($geschlecht == 'w') { echo 'selected="selected"'; } ?>> w

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<?

function output_selection($var,$value)
{
  if ($var==$value)
    echo " checked=\"checked\"";
}

?>

<form>
  <input type="radio" name="geschlecht" value="m"<? output_selection($geschlecht,"m"); ?>> m
  <input type="radio" name="geschlecht" value="w"<? output_selection($geschlecht,"w"); ?>> w
  <input type="submit">
</form>

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<?

function radiobox($name,$value,$text)
{
  eval("global \$$name;");
  eval("\$var=\$$name;");
  
  if ($var==$value) $checked=" checked=\"checked\"";

  echo "  <input type=\"radio\" name=\"$name\" value=\"$value\"$checked> $text\n";
}

echo "<form>\n";

radiobox("geschlecht","m","männlich");
radiobox("geschlecht","w","weiblich");

echo "  <input type=\"submit\" value=\"OK\">\n";
echo "</form>\n";

?>