1.剪切板：
    Clipboard.SetDataObject(textBox1.SelectedText);
    2.时间格式：
        DateTime time = new DateTime(2015,9,17,9,50,34);
        Console.WriteLine(time.ToString("yyyy-MM-dd HH:mm"));
    3.连接Mysql字符串：Database="+database+";Data Source=localhost;User Id=root;Password=;CharSet=utf8
    4.winform读取配置文件：System.Configuration.ConfigurationSettings.AppSettings["database"]
    5.datatable选取单列：
        var tablenames = table.AsEnumerable().Select(t => new { TABLE_NAME = t.Field<string>("TABLE_NAME") });
                    List<string> tabs = new List<string>();
                    foreach (var item in tablenames)
                    {
                        if (!tabs.Contains(item.TABLE_NAME))
                            tabs.Add(item.TABLE_NAME);  
                    }
    6.List<string>批量添加数据：
              List<string> biaoshi1 = new List<string>() { "第一条", "第二条", "第三条", "第四条", "第五条" };
              biaoshi1.AddRange(new string[] { "第十六条", "第十七条", "第十八条"}.ToList());
    7.数组合并：
            result.Concat(item);
    8.DataTable过滤，增加属性：
        1.新增属性： table.ExtendedProperties.Add("errormsg", errorkey);
        2.过滤:              rows=MsgTable.Select("准考证号=\'" + ScoreTable.Rows[n]["考号"].ToString().Trim() + "\'");
    9.DataView过滤，排序：
         sort_view = ScoreTable.DefaultView;
         sort_view.RowFilter = "考号<>\'\'";
         sort_view.Sort = "考号 asc";
         DataTable scoretab2 = sort_view.ToTable();
    10.打开文件：
         System.Diagnostics.Process.Start(item.ToString());
    11.格式化两位小数：
        log_builder.Insert(0,"考生成绩总数:"+ScoreTable.Rows.Count.ToString()+"\r\n可匹配考生数：" + totalcount.ToString() + "\r\n匹配率：" + string.Format("{0:F}", ((decimal)totalcount / (decimal)ScoreTable.Rows.Count)*100) + "%\r\n");
    12.正则匹配：
        Regex Catalog_regex = new Regex(@"\b第\w*章\b.+\t\b");
                    MatchCollection matches = Catalog_regex.Matches(Catalog);
                    List<string> Catalog_list = new List<string>();
                    if (matches.Count > 0)
                    {
                        foreach (var item in matches)
                        {
                            Catalog_list.Add(item.ToString().Replace("\t",""));
                        }
                    }
    13.字符串查找数字：
        Regex regex = new Regex(@"\d+");
                    
                    foreach (string item in keys)
                    {
                        filelist = FBY_libs.Oper.File_Oper.GetFileNames(this.process_textBox.Text.Trim(), "*" + item + "*.XLS", true).ToList();
                        foreach (string str in filelist)
                        {
                            filename = Path.GetFileNameWithoutExtension(str);
                            this.result_textBox.Text += filename + "\t\t" + regex.Match(filename).Value+"\r\n";
                        }
                        this.result_textBox.Text += "\r\n";               
                    }
    14.主线程休眠：
        System.Threading.Thread.Sleep(1000);
    15.创建文件夹：
         Directory.CreateDirectory(out_path + "\\" + item);
    16.Word模板关联数据：
         //域参数
                    string[] Filed_vars=new string[table.Columns.Count];
                    object[] Filed_values = new object[table.Columns.Count];
                    for (int n = 0; n < table.Columns.Count; n++)
                    {
                        Filed_vars[n] = table.Columns[n].ColumnName;
                    }
                    for (int n = 0; n < table.Rows.Count; n++)
                    {
                        doc = new Document(templet);
                        for (int t = 0; t < table.Columns.Count; t++)
                        {
                            Filed_values[t] = table.Rows[n][t];
                        }
                        doc.MailMerge.Execute(Filed_vars, Filed_values);
                        doc.Save(out_path+filename+"-"+(n+1).ToString()+".docx",SaveFormat.Docx);
                    }
    17.Word批量合并：
         //合并word
                    Document total_doc = new Document(out_path + filename + "-" + "1.docx");
        
                    for (int n = 2; n <= table.Rows.Count; n++)
                    {
                        doc = new Document(out_path + filename + "-" + n.ToString()+".docx");
                        
                        total_doc.AppendDocument(doc, ImportFormatMode.KeepSourceFormatting);
                    }
                    total_doc.Save(out_path+filename+"-"+"汇总.docx");
                    for (int n = 1; n <= table.Rows.Count; n++)
                    {
                        File.Delete(out_path + filename + "-" + n.ToString() + ".docx");
                    }
    18.验证文件存在：
            if (!File.Exists(this.Catalog_path_textBox.Text.Trim()))
                    {
                        MessageBox.Show("目录页文件不存在，请检查！","提示");
                        return;
                    }
    19.窗体快捷键：
        首先要将form窗体的KeyPreview属性设为True。
        if (e.KeyCode == Keys.F1)
                    {
                        ShowHelp();
                    }
    20.Dictionary的linq查询：
        var sel = from d in dict2.AsEnumerable() where d.Value == row["医师资格证书编码"].ToString() select d.Key;
        foreach (int key2 in sel.ToList())
                   {
                     table.Rows[key2]["当前状态"] = "免考";
                    }
    21.删除文件及文件夹：
         if (Directory.Exists(page_path))
                        Directory.Delete(page_path,true);
    22.DataTable删除：
        datatable.Rows[i].Delete();
        Datatable.AcceptChanges();
    23.随机List<T>:
         public List<T> RandomSortList<T>(List<T> ListT)  
                {  
                    Random random = new Random();  
                    List<T> newList = new List<T>();  
                    foreach (T item in ListT)  
                    {  
                        newList.Insert(random.Next(newList.Count), item);  
                    }  
                    return newList;  
                }  
    24.NPOI设置单元格样式：
        if (Convert.ToInt32(t_row.ItemArray[5]) < 60)
                                    {
                                       ICellStyle cellStyle = result_xls.CreateCellStyle();
                                       IFont font=result_xls.CreateFont();
                                       font.Color = 10;
                                       cellStyle.SetFont(font);
                                       
                                       cell.CellStyle = cellStyle;
                                     }
    25.Linq查询:
          trueanswer = answer.Where(x => x.Option == result["Answer"].ToString()).ToList();