WinForm常用代码

//ToolStripSplitButton是标准按钮和下拉按钮的组合，各自工作，但有联系，感觉上后者是没有向下箭头ToolStripDropDownButton；
ToolStripDropDownButton只含有一个按钮，可以选择有没有向下箭头的标志，单击时显示关联的 ToolStripDropDown 的控件。两者均可改变箭头标志在做还是在右。//VS自带双缓冲this.SetStyle(ControlStyles.UserPaint | ControlStyles.AllPaintingInWmPaint |ControlStyles.OptimizedDoubleBuffer, true);//控件双缓冲Control.DoubleBuffered=true; //attribute modfied by PRotected//手工双缓冲Bitmap bmp = new Bitmap(600, 600);Graphics g = Graphics.FromImage(bmp);g.DrawLine();this.CreateGraphics().DrawImage(bmp, 0, 0);//这句是关键，不能在OnPaint里画BitBmp在这里调InvalidateInvalidate(Rectangle)//规定区域重绘，解决闪烁的另一种方法ComboBox ComboBox1 = (ComboBox) sender;(Sender as SomeObject).Method()this.label1.Font = new System.Drawing.Font("微软雅黑", 72F, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, ((byte)(134)));this.label1.Font = new Font("微软雅黑", fontSize);//自定义控件背景透明SetStyle(ControlStyles.UserPaint, true);SetStyle(ControlStyles.SupportsTransparentBackColor, true);this.BackColor = Color.Transparent;//获得程序集System.Reflection.Assembly assem = System.Reflection.Assembly.GetExecutingAssembly();//点移位Point.Offset(Point);Point.Offset(int,int);Rectangle.Contains(Point);//截获标题栏消息，自画标题栏using System.Runtime.InteropServices;using System.Drawing.Drawing2D;[DllImport("user32.dll")]private static extern IntPtr GetWindowDC(IntPtr hWnd);[DllImport("user32.dll")]private static extern int ReleaseDC(IntPtr hWnd, IntPtr hDC);private const int WM_NCPAINT = 0x0085;private const int WM_NCACTIVATE = 0x0086;private const int WM_NCLBUTTONDOWN = 0x00A1;protected override void WndProc(ref Message m){    base.WndProc(ref m);    Rectangle vRectangle = new Rectangle((Width - 75) / 2, 3, 75, 25);    switch (m.Msg)    {        case WM_NCPAINT:        case WM_NCACTIVATE:            IntPtr vHandle = GetWindowDC(m.HWnd);            Graphics vGraphics = Graphics.FromHdc(vHandle);            vGraphics.FillRectangle(new LinearGradientBrush(vRectangle,                 Color.Pink, Color.Purple, LinearGradientMode.BackwardDiagonal),                vRectangle);                        StringFormat vStringFormat = new StringFormat();            vStringFormat.Alignment = StringAlignment.Center;            vStringFormat.LineAlignment = StringAlignment.Center;            vGraphics.DrawString("About", Font, Brushes.BlanchedAlmond,                 vRectangle, vStringFormat);            vGraphics.Dispose();            ReleaseDC(m.HWnd, vHandle);            break;        case WM_NCLBUTTONDOWN:            Point vPoint = new Point((int)m.LParam);            vPoint.Offset(-Left, -Top);            if (vRectangle.Contains(vPoint))                MessageBox.Show(vPoint.ToString());            break;    }}Control.SuspendLayout;//在它和ResumeLayout之间的代码不会引起Parent Control的重绘Control.AddRange(new Control[]{});//添加多个控件Control.ResumeLayout;// 在它和SuspendLayout之间的代码不会引起Parent Control的重绘Button[] buttons = new Button[] {};//大胆地设类数组吧~Button.SetBounds(int,int,int,int);//设置Button的左、右、宽、高；//应该尽可能地用Anchor、Dock，特殊情况下用Layout事件Form.MdiParent=(Form);//设置MDI父窗口//Active事件里this.Hide()是正道Form.Show();Form.Text=”Mytext”;//这两句的顺序不能//static不能修饰临时变量，一般用来修饰类变量（不是类的对象实例变量！！！）Form.MdiParent = this;Form.TopLevel = true;Form.IsMdiContainer= true;Form. ActivateMdiChild//sqlconnection连接字符串@"Data Source= ./SQLEXPRESS;AttachDBFilename=C:/../*.MDF;Integrated Security=True;User Instance=True"))//sqlconnection连接的基本步骤using System.Data.SqlClient;Dataset dataset = new DataSet();using (SqlConnection conn = new SqlConnection(@"Data Source= ./SQLEXPRESS;AttachDBFilename=C:/SQL Server 2000 Sample Databases/NORTHWND.MDF;Integrated Security=True;User Instance=True")){conn.Open();SqlDataAdapter adapter = new SqlDataAdapter(conn.CreateCommand());    adapter.SelectCommand.CommandText = "select * from customers";adapter.Fill(dataset);foreach (DataRow row in dataset.Tables[0].Rows){string item=row["ContactTitle"]+","+row["ContactName"];    listBox1.Items.Add(item);}}ListBox.Items.Add（new string）//ListBox添加项//创建DataSet中的记录DataRow row = DataSet.Tables[0].NewRow();row["**"] =***;dataset.Tables[0].Rows.Add(row);//更新DataSetDataRow row=DataSet.Table[0].Rows[index];row[“***”]=***;//删除DataSet中的记录DataSet.Tables[0].Rows.Remove(DataSet.Table[0].Rows[index]);//DataRow.Delete()和DataSet.Tables[0].Rows.Remove()不一样,后者是从DataSet中彻底删除DataRow row=DataSet.Table[0].Rows[index];row[“***”]=***;row.delete();TYPE varable=row[“***”,DataRowVersion.Original]// DataRow的完整访问方式和DataRow.RowStateSwitch (row.RowState){case DataRowState.Deleted:    	row["***", DataRowVersion.Original];    case DataRowState.Added:    	row["["***"]    case DataRowState.Modified:    	row["***", DataRowVersion.Original]       	row["***", DataRowVersion.Current]case DataRowVersion.Unchanged:    	row["***"]}//获取部分特定状态的数据集DataTable modifiedTable = DataSet.Tables[0].GetChanges(DataRowState.Added| DataRowState.Modified| DataRowState.Deleted);//创建数据库查询连接适配器的几种方式SqlDataAdapter  adapter = new SqlDataAdapter("select * from TABLENAME", SqlConnection); //最简单SqlDataAdapter adapter = new SqlDataAdapter(SqlConnection.CreateCommand());adapter.SelectCommand.CommandText = "select * from TABLENAME ";SqlDataAdapter  adapter = new sqldat SqlDataAdapter();adapter.SelectCommand = new SqlCommand("select * from TABLENAME ", SqlConnection);//万能的数据集更新器SqlCommandBuilderSqlDataAdapter adapter = new SqlDataAdapter("select * from TABLENAME ", SqlConnection);new SqlCommandBuilder(adapter);try{adapter.Update(modifiedDataSet);PoulateListBox();}catch (System.Exception ex){}//多表数据集建议分别创建适配器SqlDataAdapter  adapter1 = new SqlDataAdapter("select * from TABLENAME", SqlConnection); adapter1.Fill(DataSet,”TABLENAME1”);SqlDataAdapter  adapter2 = new SqlDataAdapter("select * from TABLENAME", SqlConnection); adapter2.Fill(DataSet,”TABLENAME2”);////Make some changes to the DataSet .TABLENAME1 or DataSet .TABLENAME2//new SqlCommandBuilder(adapter1);adapter1.Update(DataSet,” TABLENAME1”);new SqlCommandBuilder(adapter2);adapter2.Update(DataSet,” TABLENAME2”);//创建DataSet自带约束UniqueConstraint constrint = new UniqueConstraint(DataTable.Columns["***"]);//唯一性约束DataTable.Constraints.Add(constrint);//外键约束：ForeignKeyConstraint//关系基于两张表的两个列上，添加于两张表共属的数据集，并且自动生成分别在两个表上生成UniqueConstraint 和ForeignKeyConstraintDataRelation relation = new DataRelation("CustomersOrders", DataTable.Columns["***"], DataTable.Columns["***"]);dataset.Relations.Add(relation);Form.Modal//判断显示方式是模式还是非模式，模式为true，非模式为false，只有在Load事件中和之后该属性才有实际意义，在构造期间默认为falsemyForm.Control1.Text=”Data put in by a user”;//这样不好,封装性不强不易维护更新，用下面的pulbic String Control1Text{	get{		return Control1.Text;}Set{	Control1.Text;=value;}}//…myForm. Control1Text=” Data put in by a user”;//DialogResult res=ShowDialog()只是获取对话框结果的快捷方式，完整方式如下void someButton_Click(object sender,EventArgs e){this.DialogResult=DialogResult.Retry;	this.close();}someForm=new someForm();someForm.showDialog();DialogResult ref= someForm .DialogResult;if(ref= DialogResult.Retry)//…string path =Directory.GetCurrentDirectory();System.IO.FileStream aFile = new System.IO.FileStream(path, FileMode.Open);StreamReader sr = new StreamReader(aFile, System.Text.Encoding.Default);/*对于每个关联的 SqlConnection，一次只能打开一个 SqlDataReaderSqlConnection 与 SqlDataAdapter 和 SqlCommand 一起使用，可以在连接 Microsoft SQL Server 数据库时提高性能。对于所有第三方 SQL 服务器产品以及其他支持 OLE DB 的数据源，请使用 OleDbConnection。SqlConnection 超出范围，则不会将其关闭。因此，必须通过调用 Close 或 Dispose 显式关闭该连接。最好在using 块内部打开连接。连接自字符串关键字不区分大小写，并将忽略键/值对之间的空格。 不过，根据数据源的不同，值可能是区分大小写的。 任何包含分号、单引号或双引号的值必须用双引号引起来。*/System.Data.SqlClient.SqlConnectionStringBuilder builder =new System.Data.SqlClient.SqlConnectionStringBuilder();builder["Data Source"] = "(local)";builder["integrated Security"] = true;builder["Initial Catalog"] = "AdventureWorks;NewValue=Bad";// 使用System.Data.SqlClient.SqlConnectionStringBuilder不需要担心分号、单引号或双引号的转义问题Console.WriteLine(builder.ConnectionString);//打开数据库的某个古老方法SqlConnection mc=new SqlConnection();mc.ConnectionString=”/*…*/”;mc.Open();//有关SqlCommand, SqlDataReader的基本使用SqlCommand scm=SqlConnection.CreateCommand();scm.CommandText=”select */*…*/”;SqlDataReader sdr=scm.ExecuteReader();sdr.Read();//…sdr.close();//以ToolStrip为例绘制简便背景e.Graphics.FillRectangle(new System.Drawing.Drawing2D.LinearGradientBrush(new System.Drawing.Point(0, toolStrip1.Height),new System.Drawing.Point(0, 0), Color.FromKnownColor(KnownColor.ControlDark), Color.FromKnownColor(KnownColor.ControlLight)), toolStrip1.ClientRectangle);//获取Color的几种方式Color.FromKnownColor(KnownColor.ControlLight);Color.FromArgb(int r,int g,int b);Color.FromArgb(int a,int r,int g,int b);//a表示透明度，0-255，0为全透明，255为不透明，