/// <summary>
/// 要保存的文件路径
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void btnSavePath_Click(object sender, EventArgs e)
{
    FolderBrowserDialog dialog = new FolderBrowserDialog();
    if (dialog.ShowDialog() == DialogResult.OK)
    {
        if (string.IsNullOrEmpty(dialog.SelectedPath)) { MessageBox.Show("路径不能为空"); return; }
        lblTxtSavePath.Text = dialog.SelectedPath;
    }
}
/// <summary>
/// 开始执行比对
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void btnDo_Click(object sender, EventArgs e)
{
    //要保存的txt文件名称
    string txtFileName = txtSaveName.Text.Trim();
    if (txtFileName.Length <= 0) { MessageBox.Show("txt文件名称不能为空"); return; }
    if (!txtFileName.EndsWith(".txt")) txtFileName = lblTxtSavePath.Text + "\\" + txtFileName + ".txt";
    //当前查询截止的目录
    string currPath = lblTxtSavePath.Text + "\\" + "currPath.txt";

    //要搜索的文件夹路径
    string searchPaths = txtSearchPath.Text.Trim();
    if (searchPaths.Length <= 0) { MessageBox.Show("要搜索的文件夹路径不能为空"); return; }
    string[] searchPathArr = searchPaths.Split(‘,‘);

    //禁用当前按钮 防止重复执行
    DisableFormControls();

    Task.Factory.StartNew(() =>
    {
        //最终服务器上图片不在数据库中的路径
        List<string> imageTargetUrls = new List<string>();

        //从数据库中读取 [Type=‘房源‘ OR Type=‘楼盘‘] 的图片地址
        DataTable dtUrl = GetData();

        if (dtUrl != null && dtUrl.Rows.Count > 0)
        {
            //从要搜索的文件夹路径中找出所有的图片及其路径 key=路径 value=值
            //Dictionary<string, string> imageDic = new Dictionary<string, string>();
            if (searchPathArr != null && searchPathArr.Length > 0)
            {
                foreach (var path in searchPathArr)
                {
                    if (Directory.Exists(path))
                    {
                        getFile(path, ".jpg.JPEG.PNG.bmp.png.GIF", dtUrl, txtFileName, currPath);
                    }
                }
            }
        }

        Invoke(new Action(() => { EnableFormControls(); MessageBox.Show(this, "执行完成"); }));
    });
}
/// <summary>
/// 禁用当前窗口的可操作控件
/// </summary>
private void DisableFormControls()
{
    btnDo.Enabled = false;
    btnSavePath.Enabled = false;
    txtSaveName.Enabled = false;
    txtSearchPath.Enabled = false;
}

/// <summary>
/// 启用当前窗口的可操作控件
/// </summary>
private void EnableFormControls()
{
    btnDo.Enabled = true;
    btnSavePath.Enabled = true;
    txtSaveName.Enabled = true;
    txtSearchPath.Enabled = true;
}

/// <summary>
/// 从数据库获取数据
/// </summary>
private static DataTable GetData()
{
    DataTable dt = null;
    string str_sql_conn = ConfigurationManager.AppSettings["sql_connect_str"];
    using (SqlHelper conn = new SqlHelper(str_sql_conn))
    {
        string sql_text = @"SELECT URL FROM dbo.T_Attachment WHERE Type=‘房源‘ OR Type=‘楼盘‘";
        dt = conn.ExecuteDs(sql_text, CommandType.Text, null).Tables[0];
    }
    return dt;
}
/// <summary>
/// 获得目录下所有文件或指定文件类型文件(包含所有子文件夹)
/// 记录当前查询截止的目录(防止程序崩溃 下次从这个地方重启)
/// 查询当前目录是否在数据库中被引用
/// 记录当前查询截止的文件地址(防止程序崩溃 下次从这个地方重启)
/// 查询当前目录下的图片是否在数据库中被引用
/// 记录未被数据库引用的图片的路径
/// </summary>
/// <param name="path"></param>
/// <param name="extName"></param>
/// <param name="dtUrl"></param>
/// <param name="txtFileName"></param>
/// <param name="currPath"></param>
public static void getFile(string path, string extName, DataTable dtUrl, string txtFileName, string currPath)
{
    try
    {
        //记录当前查到了哪个文件夹
        File.AppendAllLines(currPath, new string[] { path });

        //判断当前路径是否在数据库中有引用 如果不存在 不需要判断当前目录下的子目录及子文件
        string dictionaryLastName = path.Split(new string[] { "\\upload" }, StringSplitOptions.None)[1].Replace("\\", "/");
        if (!dtUrl.AsEnumerable().Any(s => s.Field<string>("URL").ToLower().Contains(dictionaryLastName.ToLower())))
        {
            File.AppendAllLines(txtFileName, new string[] { path });
            return;
        }

        string[] dir = Directory.GetDirectories(path); //文件夹列表
        DirectoryInfo fdir = new DirectoryInfo(path);
        FileInfo[] file = fdir.GetFiles();
        if (file.Length != 0 || dir.Length != 0) //当前目录文件或文件夹不为空
        {
            foreach (FileInfo f in file) //显示当前目录所有文件
            {
                //判断是否为图片
                if (extName.ToLower().IndexOf(f.Extension.ToLower()) >= 0)
                {
                    //记录当前查到了哪个图片文件
                    File.AppendAllLines(currPath, new string[] { f.FullName });

                    //判断当前文件是否在数据库中被引用
                    if (!dtUrl.AsEnumerable().Any(s => s.Field<string>("URL").ToLower().Contains(f.Name.ToLower())))
                    {//数据库中不包含服务器上文件夹中的图片
                     //记录下当前图片的路径
                        File.AppendAllLines(txtFileName, new string[] { f.FullName });
                    }
                }
            }

            foreach (string d in dir)
            {
                getFile(d, extName, dtUrl, txtFileName,currPath);//递归
            }
        }
    }
    catch (Exception ex)
    {
        throw ex;
    }
}