WPF：图像处理（一）图像文件获取与预览(2)

                return FileEntries; 
 
            // 建立正则表达式 
            Regex rx = new Regex(filter, RegexOptions.IgnoreCase); 
 
            // 过滤文件 
            List<String> FilterFileEntries = new List<String>(FileEntries.Length);             
            foreach (String FileName in FileEntries) 
            { 
                if (rx.IsMatch(FileName)) 
                { 
                    FilterFileEntries.Add(FileName); 
                } 
            } 
 
            return (FilterFileEntries.Count == 0) ? null : FilterFileEntries.ToArray();             
        } 
 
        /// <summary> 
        /// 返回指定目录中图像文件列表，并使用一个值以确定是否搜索子目录 
        /// </summary> 
        /// <param name="folderPath">将从其检索文件的目录</param> 
        /// <param name="searchOption">指定搜索操作应包括所有子目录还是仅包括当前目录</param> 
        /// <returns>图像文件列表</returns> 
        public static String[] GetImages(String folderPath, SearchOption searchOption) 
        { 
            String filter = "\\.(bmp|gif|jpg|jpe|png|tiff|tif)$"; 
            return GetFiles(folderPath, filter, searchOption); 
        } 
 
        /// <summary>