System.Windows.Forms.DataObject.ContainsFileDropList C# (CSharp) Method

        public virtual bool ContainsFileDropList()
        {
            return false;
        }

        /// <summary>
        /// 获得拖放列表中符合要求的拖放项
        /// </summary>
        /// <param name="data">拖放数据</param>
        /// <param name="enableFolder">是否允许文件夹</param>
        /// <param name="enableFile">是否允许文件</param>
        /// <param name="fileExtensions">允许的文件类型</param>
        /// <returns>返回符合要求的文件列表</returns>
        public static IEnumerable <string> GetAvailableFileItem(this DataObject data, bool enableFolder, bool enableFile, HashSet <string> fileExtensions = null)
        {
            if (!data.ContainsFileDropList())
            {
                return(null);
            }

            return(data.GetFileDropList().Cast <string>().Where(
                       s =>
                       (enableFolder && System.IO.Directory.Exists(s))
                       ||
                       (enableFile && System.IO.File.Exists(s) && (fileExtensions == null || fileExtensions.Count == 0 || fileExtensions.Contains("*") || fileExtensions.Contains(System.IO.Path.GetExtension(s).Trim('.'))))
                       ));
        }