javascript - 如何使用 Greasemonkey 编辑 HTML <select> 元素？

Question

有一款神奇宝贝战斗模拟器，名为“神奇宝贝对决”。客户端是闭源的，所以我无法向我的服务器添加层。我想编辑最终战斗下拉列表以添加等级。

我想改变:

<select id="lobby-format" onchange="return rooms['lobby'].formSelectFormat()">
  <option value="randombattle" selected="selected">Random Battle (rated)</option>
  <option value="unratedrandombattle">Unrated Random Battle</option>
  <option value="ou">OU (rated)</option>
  <option value="cap">CAP (rated)</option>
  <option value="ubers">Ubers (rated)</option>
  <option value="uu">UU (rated)</option>
  <option value="ru">RU (rated)</option>
  <option value="nu">NU (rated)</option>
  <option value="lc">LC (rated)</option>
  <option value="hackmons">Hackmons (rated)</option>
  <option value="balancedhackmons">Balanced Hackmons (rated)</option>
  <option value="glitchmons">Glitchmons (rated)</option>
</select>

至:

<select id="lobby-format" onchange="return rooms['lobby'].formSelectFormat()">
  <option value="randombattle" selected="selected">Random Battle (rated) </option>
  <option value="unratedrandombattle">Unrated Random Battle</option>
  <option value="ou">OU (rated)</option>
  <option value="cap">CAP (rated)</option>
  <option value="ubers">Ubers (rated)</option>
  <option value="uu">UU (rated)</option>
  <option value="ru">RU (rated)</option>
  <option value="nu">NU (rated)</option>
  <option value="pu">PU (unrated)</option>
  <option value="lc">LC (rated)</option>
  <option value="bwcup">BW Cup (unrated)</option>
  <option value="hackmons">Hackmons (rated)</option>
  <option value="balancedhackmons">Balanced Hackmons (rated)</option>
  <option value="glitchmons">Glitchmons (rated)</option>
</select>

(在选定位置插入 2 <options>。)

Answer 1

好的，尝试一下:

var opt = document.createElement("option");

var content = document.createTextNode("PU (unrated)");
opt.appendChild(content);

var attr = document.createAttribute("value");
attr.nodeValue = "pu";
opt.setAttributeNode(attr);

var targetEl = document.getElementById("lobby-format");
targetEl.appendChild(opt);

这只会再添加一个选项，但我想您已经明白了。