/// <summary>获取 <see cref="T:System.Collections.SortedList" /> 对象中的键。</summary> /// <returns>包含 <see cref="T:System.Collections.SortedList" /> 对象中的键的 <see cref="T:System.Collections.IList" /> 对象。</returns> /// <filterpriority>2</filterpriority> public virtual IList GetKeyList() { if (this.keyList == null) { this.keyList = new SortedList.KeyList(this); } return((IList)this.keyList); }