创建动态菜单或下拉列表的JavaScript代码

function makeMenu(items, tags) {
  tags = tags || ['ul', 'li']; // default tags
  var parent = tags[0];  var child = tags[1]; 
  var item, value = &#39;&#39;;  for (var i = 0, l = items.length; i < l; i++) {
    item = items[i];    // Separate item and value if value is present
    if (/:/.test(item)) {
      item = items[i].split(&#39;:&#39;)[0];
      value = items[i].split(&#39;:&#39;)[1];
    }    // Wrap the item in tag
    items[i] = &#39;<&#39;+ child +&#39; &#39;+
      (value && &#39;value="&#39;+value+&#39;"&#39;) +&#39;>&#39;+ // add value if present
        item +&#39;</&#39;+ child +&#39;>&#39;;
  } 
  return &#39;<&#39;+ parent +&#39;>&#39;+ items.join(&#39;&#39;) +&#39;</&#39;+ parent +&#39;>&#39;;
}

// Dropdown select monthmakeMenu(
  ['January:JAN', 'February:FEB', 'March:MAR'], // item:value
  ['select', 'option']
); 
// List of groceriesmakeMenu(
  ['Carrots', 'Lettuce', 'Tomatos', 'Milk'],
  ['ol', 'li']
);