I need to create a text editing control in C# and I'm not sure where to start.
For a bit of context: a C# program is going to edit an XML document (using this control). The XML document can be converted to HTML.
The XML document will contain the following:
Normal text (obviously)
Headings (which will be formatted differently)
Lists
Images
Videos (they don't need to be viewed in the control, but there needs to be a box or something to indicate that they're there)
I want this control to take the XML and render it and act as an WYSIWYG editor for the XML.
For the moment, I'm not to concerned about implementing all the above details (although they will need to be implemented eventually), I just want to know where to start with creating this control. Should I be inheriting from TextBoxBase (or TextBox) and going from there? And what methods would I need to override? Or should I inherit from Control (in which case I think I'd need to all the text box stuff - selecting text, copy and paste, the caret etc. - myself, which is something I don't really want to do, but I am prepared to do if I have to).
I am aware of preexisting controls like TX Text Control that do something like what I want (although this one is far more powerful than I need), but I can't use these (this is for a university project), and besides, I really do want to know how to make this from scratch.
The topic of creating a feature rich edition control with syntax highlighting, code completion, etc. has been discussed by the developers of #develop in their book "dissecting a C# Application"
http://www.icsharpcode.net/OpenSource/SD/InsideSharpDevelop.aspx
(I think you can't buy it anymore, the link says it's available for free to download but the links seems to be broken)
The book basically explain the core features of #develop (pre V1, so it's kinda outdated), including the code editor and (what is important, too) which mistakes they made during the process.
Should I be inheriting from TextBoxBase (or TextBox) and going from there?
You can't inherit from TextBoxBase (its constructor is internal).
So you can inherit from TextBox or from Control or UserControl.
The problem with TextBox is that its painting is done by unmanaged code, which isn't overridden when you override OnPaint. For further details, see this question, answer and comments.
I am aware of preexisting controls like TX Text Control that do something like what I want
The TX Text Control is something else: it's implemented using Win32 code, with a .NET wrapper/API.
A few years ago I used the excellent open source Scintilla editor as a base to derive a custom C# control from. Worked great. Nowadays it's even easier if you leverage the ScintellaNET project (CodePlex) which has already done the wrapper work for you. Of course, if you don't mind paying, you can't go wrong with Actipro's SyntaxEditor.
Inheriting from Control will require lots of work, such as painting, implementing default behaviour, etc..
I think you can start with studying RichTextBox control because all of your requirements can be done by changing RichtextBox control.
Related
I was trying to do something in visual studio the other day when I realized, if I could just make a form control to do it for me it would be allot easier, except I have no idea how to do that, I want the form control to have grids, each square having its own color property, if anyone knows how to make form controls, or even better knows how to make something like what I just described, I would be very happy :D
This MSDN article is a basic step by step outline of how you can write a customer control.
Unfortunatly MS has not figured out how to do avoid link rot -- so you may need to search creating custom winform controls to find this if you come in the future.
You are usually best servered by subclassing an existing control and customizing it.
You might also find some of the freely available winform control projects a gold-mine of useful info if you get serious about this.
However, it sounds likely what you should consider doing is creating a "User Control", this is usually simpler for a composite of few existing controls. This
article on the types of controls for winforms may be a useful overview for you.
Beyond that you really should use S/O if you are trying to resolve a specific problem you are having when you are coding. Google is a more appropriate tool for finding tutorials, etc.
1) Inside your project: Solution Explorer --> Right Click the .csproj --> Add UserControl
2) Drag and drop gridBox or any control you want into your custom control.
3) Check the ToolBox, your custom control should be located at the very first selection
Using C# winforms, i want to create custom controls that looks like the real ones.
There are a lot of classes that can be used to draw controls that looks like the real ones: ControlPaint, VisualStyleRenderer, ButtonRenderer, CheckBoxRenderer, ComboBoxRenderer, GroupBoxRenderer, ProgressBarRenderer, RadioButtonRenderer, ScrollBarRenderer, TabRenderer, TextBoxRenderer, TextRenderer, ToolStripProfessionalRenderer, ToolStripRenderer, ToolStripSystemRenderer, TrackBarRenderer.
The problems coming when considering visual styles: I want to be visual styles independent. Meaning: I dont care if user allowing visual-styles or not, i want it to work. if user enabled visual-styles, i want to draw it using visual-styles, otherwise i want to draw it without visual-styles.
By the MSDN documentation, the only classes that are visual-styles independent are ButtonRenderer, CheckBoxRenderer, GroupBoxRenderer, RadioButtonRenderer. That means that for all other cases i need to check myself if visual-styles enabled and use different code to draw the parts.
Suppose i want to draw a Tab control parts myself. TabRenderer class has all needed functionality for that, but it works only if user enabled visual styles. otherwise I need to use ControlPaint class to draw, but it uses completely different model, there is no ControlPaint.DrawTab() method or something like that, and i need to figure out what rectangle types i need to draw so it will look like a real tab. that`s annoying.
The built-in controls, including the Tab control, already have this functionality of drawing themselves with or without visual styles. Why doesn`t microsoft exposing this functionality for the custom control creators? Why are custom control creators should suffer?
It's a pain unfortunately, but that is the cost for writing custom controls. The way I have seen Microsoft do this in many of the WinForm controls, is to check Application.RenderWithVisualStyes, and Control.UseVisualStyleBackColor. Depending on those values they will paint the control accordingly.
A common pattern they use is to create internal classes called MyControlRenderer.cs. Inside this renderer is where the magic actually happens. If you look at the NET REF code, you will see that they also use VisualStyleRenderer class from System.Windows.Forms.VisualStyles namespace, and there is some actual paint code as well.
You will need to utilize a mix of these various classes and tools, and a mix of also doing your own work. Testing your control on a machine with, and without visual styles.
When I hope home from work I will post a bit more.
how i integrate html text editor in windows application?
The best option would be to use a commercial syntax highlighting package, such as Actipro SyntaxEditor.
You can just use a RichTextBox and do it yourself, but it is going to be more difficult to make this seem polished. There are some articles, such as the CodeProject article, which show how to extend RichTextBox for custom editing and coloring. That would be a good starting point, if you want to make your own.
If you just want a place people can type HTML in, but don't need coloring, syntax checking, etc - you can just use a RichTextBox and let the user type in the HTML.
I am looking for a free WYSIWYG editor control to be used in a Winform application. The applications primary language is VB but using C# is also an option. To clarify I need a rich text editor control that has a formatting bar. I have looked all over the web and the only options I can find are expensive control packages that have more than I need. I am not adverse to creating my own version of this control, it would just be nice to find a free and open alternative.
In this scenario, starting with CodeProject articles seems the easiest:
http://www.codeproject.com/KB/edit/editor_in_windows_forms.aspx -- Not my first recommendation, but perhaps of use if you want HTML.
http://www.codeproject.com/KB/edit/TextRulerControl.aspx?fid=968441&df=90&mpp=25&noise=3&sort=Position&view=Quick&fr=26&select=2438044
http://www.codeproject.com/KB/cs/eRichTextBox.aspx
Actually it's very easy to write your own based on the RichTextBox control.
I would go that way for sure. Your biggest problem will be the icons for the edit bar.
Check this one for starter.
Im looking to create a custom ASP.NET container control that will allow me to drag further controls into it within the VS designer.
The final HTML that im looking for is very simple..
<div id="panel1">
<div id="panel2">
</div>
<div id="panel2">
</div>
</div>
With additional controls being able to be dragged into panels 2 and 3.
Im sure its very simple but im struggling to find examples that will help.
Any pointers or ideas are appreciated!
Cheers
Stuart
I've done such things in the past, and yes, from my experience at that time there is not much documentation available. Even worse, at that time some of the documentation was incorrect or vague!
So, to save you all the headaches (ouch, it already starts to hurt when I just think of it :-P), here is some information you definitely need to know.
Basically all controls are for run-time use only. You can attach a ControlDesigner to a control with an attribute on the class definition, which the design time environment (VS.NET IDE) will load and use as a layer on top of your control.
Templates
Chris' suggestion to use Templates is in the right direction. Your control needs to store somewhere the 'content' of the div's, and Templates are the perfect solution. Make sure you get this part right at first. Note: template properties can behave weird if they have a set clause! Moreover, check the use of NotifyParentAttribute also.
When you've got the templates in place, and you can use declarative syntax in ASPX pages to add controls, and they render well, then you can start working on the designer.
For the designer you have 2 options; the easy and complex way.
Easy designer solution
Let's start with the easy way. The base ControlDesigner classes already provide a framework to show templates. You have probably already seen this in action, like in the GridView control and its template fields.
Check out the following MSDN article on creating a template control designer.
With this easy solution, you get an automatic implementation of the smart tag (the arrow to the right of a control during design-time), and can select a template to edit from a drop down list.
Complex designer solution
Now, if this is not really satisfying for you, and you would like to be able to edit controls just like a Panel control, then you have to dig deeper. So here is the complex solution using Control Designer Regions.
See the example in the example in the EditableDesignerRegion class.
What this example does, is overriding the CreateChildControls of the designer class. Remember I said the designer control is a layer on top of your run-time control? So this CreateChildControls method will run after your control's implementation. What you have to do, is mark a HTML element within your render output with a special designer region HTML attribute. In this way, the designer knows what part in your rendered control should be a region.
Now you have to instruct the IDE to assign a editor or viewer to your regions. You have to do this in the GetDesignTimeHtml(DesignerRegionCollection regions) method (notice the overloaded version of this method). As you can see, this method receives a collection of regions. You have to assign your editable of view regions to this collection. Important here - and this is the badly documented part - is that the order in this collection is very important. The value of the region attribute in your HTML, refers to the index in this collection.
So, now we have defined regions in our rendered output, assigned a editor or viewer to it. Next up is how to fill these regions and store the value from these regions back into our controls declaration.
These two actions are handled in GetEditableDesignerRegionContent and SetEditableDesignerRegionContent methods of the control designer. Here you see why it's important to name the regions that you've added to the collection in the GetDesignTimeHtml method. In these two methods you receive the region reference and by it's Name property you could determine which Template property of your control to read/write.
To read and write the template properties we use the magic of the ControlPersister and ControlParser. The persister creates an template instance from declarative ASP.NET (HTML) code. The parser does the job the other way around; creates plain HTML from a template instance.
In a nutshell
So it's up to you to decide whether the standard template editing framework is good enough for you. If you want to have fancy edit capabilities for both of your edit regions in your IDE, then you will have to implement the complex solution. Otherwise just stick with the simple implementation. The examples mentioned will help you a lot.
Here is a link to a MSDN article regarding what you are trying to do, unfortunently there is no VS designer support so it renders correctly from the server but not in the IDE.
How to: Create Templated ASP.NET User Controls
http://msdn.microsoft.com/en-us/library/36574bf6.aspx