Mono对gtk做了很努力的封装，即便如此仍然与System.Windows.Form中的控件操作方法有许多差异，这是gtk本身特性或称为特色决定的。下面是gtk常用控件在Mono C#中的一些用法。
Button控件
在工具箱中该控件的clicked信号双击后自动生成回调函数prototype，下面的函数当Button12点击后其标签名变为"Button12 is Pressed!"。还有ToggleButton，ImageButton 用法类似。
protected void OnButton12Clicked(object sender, EventArgs e)
{
Button12.Label = "Button12 is Pressed!";
}Entry控件
用法与Winform的TextBox非常相似。
protected void OnButton13Clicked(object sender, EventArgs e)
{
string sText = "";
entry2.Text = "Hello";
sText = entry2.Text;
}Checkbutton和Radiobutton
读：当选中后，它的Active属性是true ; 未选中时，它的Active属性是false。
写：Checkbutton1.Active = true; Radiobutton1.Active = true;
ColorButton颜料按钮
自动调出颜色选取dialog，用colorbutton1.Color.Red 读入红色值，或Gr
een/Blue读取绿色和蓝色值。因为调出的是dialog，所以用其它Button调用dialog功效是类同的。
protected void OnColorbutton1ColorSet(object sender, EventArgs e)
{
var redcolor = colorbutton1.Color.Red;
var greencolor = colorbutton1.Color.Green;
var bluecolor = colorbutton1.Color.Blue;
}下面是通过 ColorSelectionDialog 方式调出颜料盒对话框，用后直接dispose扔给收垃圾的，不需要destroy打砸它。C#是通过runtime执行的，不是CLR平台管理的要自己处理垃圾，自动回收是管不了的。
protected void OnButton3Clicked(object sender, EventArgs e)
{
Gtk.ColorSelectionDialog colorSelectionDialog = new Gtk.ColorSelectionDialog("Color selection dialog");
colorSelectionDialog.ColorSelection.HasOpacityControl = true;
colorSelectionDialog.ColorSelection.HasPalette = true;
colorSelectionDialog.ColorSelection.CurrentColor = StoreColor;
if (colorSelectionDialog.Run() == (int)ResponseType.Ok)
{
StoreColor = colorSelectionDialog.ColorSelection.CurrentColor;
var redcolor = colorSelectionDialog.ColorSelection.CurrentColor.Red;
var greencolor = colorSelectionDialog.ColorSelection.CurrentColor.Green;
var bluecolor = colorSelectionDialog.ColorSelection.CurrentColor.Blue;
}
colorSelectionDialog.Dispose();
}FontButton控件
它通过FontName返回字体名称、字型、字号，自动调用字体选择对话框。
protected void OnFontbutton1FontSet(object sender, EventArgs e)
{
entry1.Text = fontbutton1.FontName;
}也可以使用其它钮调用字体选择对话框，用后Dispose()掉。
protected void OnButton2Clicked(object sender, EventArgs e)
{
Gtk.FontSelectionDialog fontSelectionDialog = new Gtk.FontSelectionDialog("Font selection");
if (fontSelectionDialog.Run() == (int)ResponseType.Ok)
{
entry1.Text = fontSelectionDialog.FontName;
}
fontSelectionDialog.Dispose();
}ComboBox框
用InsertText用AppendText添加新内容，用RemoveText方法删除指定项，用Active属性选中指定项显示在显示框中。ComboBox框类似于Winform的ListBox，是不能输入的。
protected void OnButton7Clicked(object sender, EventArgs e)
{
combobox1.InsertText(0, "Item - 1");
combobox1.InsertText(0, "Item - 2");
combobox1.InsertText(0, "Item - 3");
combobox1.InsertText(0, "Item - 4");
combobox1.InsertText(0, "Item - 5");
combobox1.InsertText(0, "Item - 6");
combobox1.InsertText(0, "Item - 7");
combobox1.InsertText(0, "Item - 8");
combobox1.Active = 5;
}ComboBoxEntry框
ComboBoxEntry框是可输入的，用法同ComboBox。
TreeView列表
这框比较有特色，可显示图片和文本。图片用Gdk.Pixbuf装载，是个特殊类型。
protected void OnButton15Clicked(object sender, EventArgs e)
{
Gtk.ListStore listStore = new Gtk.ListStore(typeof(Gdk.Pixbuf), typeof(string), typeof(string));
treeview1.Model = null;
treeview1.AppendColumn("Icon", new Gtk.CellRendererPixbuf(), "pixbuf", 0);
treeview1.AppendColumn("Artist", new Gtk.CellRendererText(), "text", 1);
treeview1.AppendColumn("Title", new Gtk.CellRendererText(), "text", 2);
listStore.AppendValues(new Gdk.Pixbuf("sample.png"), "Rupert", "Yellow bananas");
treeview1.Model = listStore;
listStore.Dispose();
}DrawArea Cairo 图像
是做图用的，先创建surface,可以在内存中、图片上、pdf上、DrawArea上画图或写字，也可以存成png图片，图形可以变换座标。在内存中绘图，然后在DrawAre的context上show显示，或在其它地方显示。功能很灵活，与GDI在bitmap上做图，通过hdc显示在pictureBox上有对比性。
protected void OnButton11Clicked(object sender, EventArgs e)
{
//
// Creates an Image-based surface with with data stored in
// ARGB32 format.
//
drawingarea1Width = drawingarea1.Allocation.Width;
drawingarea1Height = drawingarea1.Allocation.Height;
ImageSurface surface = new ImageSurface(Format.ARGB32, drawingarea1Width, drawingarea1Height);
// Create a context, "using" is used here to ensure that the
// context is Disposed once we are done
//
//using (Context ctx = new Cairo.Context(surface))
using (Context ctx = Gdk.CairoHelper.Create(drawingarea1.GdkWindow))
{
// Select a font to draw with
ctx.SelectFontFace("serif", FontSlant.Normal, FontWeight.Bold);
ctx.SetFontSize(32.0);
// Select a color (blue)
ctx.SetSourceRGB(0, 0, 1);
//ctx.LineTo(new PointD(iArea1ObjX, drawingarea1.Allocation.Height));
//ctx.StrokePreserve();
// Draw
ctx.MoveTo(iArea1ObjX, iArea1ObjY);
ctx.ShowText("Hello, World");
/*
//Drawings can be save to png picture file
//surface.WriteToPng("test.png");
//Context ctxArea1 = Gdk.CairoHelper.Create(drawingarea1.GdkWindow);
//Surface surface1 = new Cairo.ImageSurface("test.png");
//Option: coordinator change, origin 0,0 is the middle of the drawingarea
//ctxArea1.Translate(drawingarea1Width / 2, drawingarea1Height / 2);
//surface.Show(ctxArea1, 0, 0);
//ctxArea1.Dispose();
*/
}
}About对话框
固定格式的对话框，有贡献者、文档人员、版权说明等，与windows的about不太相同。
protected void OnButton9Clicked(object sender, EventArgs e)
{
string[] textabout = {"abcde","fdadf","adsfasdf" };
const string LicensePath = "COPYING.txt";
Gtk.AboutDialog aboutDialog = new Gtk.AboutDialog();
aboutDialog.Title = "About mono learning";
aboutDialog.Documenters = textabout;
//aboutDialog.License = "mit license";
aboutDialog.ProgramName = "my Program";
aboutDialog.Logo = new Gdk.Pixbuf("logo.png");
//aboutDialog.LogoIconName = "logo.png";
//aboutDialog.AddButton("New-Button", 1);
aboutDialog.Artists = textabout;
aboutDialog.Authors = textabout;
aboutDialog.Comments = "This is the comments";
aboutDialog.Copyright = "The copyright";
aboutDialog.TranslatorCredits = "translators";
aboutDialog.Version = "1.12";
aboutDialog.WrapLicense = true;
aboutDialog.Website = "www.me.com";
aboutDialog.WebsiteLabel = "A website";
aboutDialog.WindowPosition = WindowPosition.Mouse;
try
{
aboutDialog.License = System.IO.File.ReadAllText(LicensePath);
}
catch (System.IO.FileNotFoundException)
{
aboutDialog.License = "Could not load license file '" + LicensePath + "'.\nGo to http://www.abcd.org";
}
aboutDialog.Run();
aboutDialog.Destroy();
aboutDialog.Dispose();
}Timer时钟
使用Glib的时钟，100ms
timerID1 = GLib.Timeout.Add(100, OnTimedEvent1);
使用System的时钟，300ms
aTimer = new System.Timers.Timer(300);
aTimer.Elapsed += OnTimedEvent;
aTimer.AutoReset = true;
aTimer.Enabled = true;
异步写文件
protected void OnButton4Clicked(object sender, EventArgs e)
{
Task r = Writedata();
async Task Writedata()
{
await Task.Run(() =>
{
VB.FileSystem.FileOpen(1, "VBNETTEST.TXT", VB.OpenMode.Output, VB.OpenAccess.Write, VB.OpenShare.Shared);
VB.FileSystem.WriteLine(1, "Hello World! - 1");
VB.FileSystem.WriteLine(1, "Hello World! - 2");
VB.FileSystem.WriteLine(1, "Hello World! - 3");
VB.FileSystem.WriteLine(1, "Hello World! - 4");
VB.FileSystem.WriteLine(1, "Hello World! - 5");
VB.FileSystem.FileClose(1);
return 0;
});
}
}
结束语
测试引用Windows.Form并创建了窗体和对话框，也能显示，但不是Linux平台原生的，不太美观且速度不理想。如果只是创建了不Show，让它处于Hide状态，比如带sort属性的ListBox，还是可以使用的。
Mono自己有许多基础库
还有DOTNET的库
还有其它第三方库
Thread和Threadpool多线程没习练，在Mono上应访不会有问题的，delegate、tuple、sqlite等与界面关系不大，就没有再去练习，毕竟mono是microsoft支持的、使用的是dotnet的库，所以相信dotnet的通用功能在mono上都不会是问题的。
--- Ubuntu20.4 mono C#试练笔记完结 ---