My typical application has a couple of textboxes, checkbuttons, radiobuttons, and so. I always want to load the settings the user used the last time when the program starts, and also want to save the settings as the users clicks "Save settings" or closes the application. When the user attempts to save the settings, I'll have to check each of the controls for input errors (sometimes they have to have a max length, other times only caps, other times other things, there isn't a rule for them all, everytime it'll be different), and only if everything's OK i'll let him save the options. If there is something wrong, no option is saved and my errorcontrol provider will pop up a description of the input type info that should be put in that control.
I've been designing this from scratch for all my projects, but it's being a pain to do it. So I'd thought maybe now was the time to do some library to help me. I thought initially that maybe it'd be a good idea to have all the controls on my form that are going to be part of this save/load process to have an attribute associated with them, something like this
public delegate bool InputIsOkHandler();
public class OptionsAttribute : Attribute {
public Control controlRef;
public InputIsOkHandler IsInputOk;
public string errorMessageToShowOnErrorProvider;
public OptionsAttribute(Control controlRef, InputIsOkHandler inputHandler, string errMessage) {
...
}
}
The main problem here is that when I declare the attribute on a given var:
[Options(...)]
TextBox textBox1 = new TextBox();
I'll get
Error 1 An attribute argument must be a constant expression, typeof expression or array creation expression of an attribute parameter type.
So I guess this approach isn't the best one. What would you guys do in this situation? Would you use attributes? Would you use other mechanisms?
Thanks
Do you know that .NET already includes such a system since 2.0? See MSDN, CodeProject and this white paper from WestWind.
The Personalization and User Profiles supported in ASP.NET 2.0 can be a nice way to achieve your goal.
You can check this MSDN article for a overview Personalization in ASP.NET 2.0
Related
Suppose I have a model with some string property.
Imagine also that this string property is actually a comma delimited list of values.
If I want to make a form to update values on my model it would be easy enough to call:
#Html.TextBoxFor(model => model.myCommaDelimitedProp, new { #class = "form-control", placeholder = "CommaDelimitedPropValue" })
However, that is not good enough for the intended application.
I would like to have a custom EditorFor() that could somehow take my property, use string parsing and next generate an array of text boxes to display the pre-existing values.
That would also be relatively trivial.
However, what I cannot seem to solve, mainly because I lack client side experience (js, jquery, angular, ...):
How could I make my editor such that there would be a small button so that I could dynamically add rows, fill them such that, upon form submission, I could string the new values onto the pre-existing string.
So specifically, what would any of you use to achieve this client side behaviour?
I just need some help to be put on the way...
You can achieve this with editor templates. There's a quick intro I threw together on my blog. The only additional thing you'll need is UIHint. Since you won't be able to rely on a specific C# type or DataType annotation to determine that this should be treated as a comma-delimited property. You can just explicitly tell Razor what template it should use. For example:
[UIHint("CommaDelimited")]
public string MyCommaDelimitedProperty { get; set; }
Which would correspond to the editor template: Views\Shared\EditorTemplates\CommaDelimited.cshtml. Once you set up that view how you like it. Then in your form you just call:
#Html.EditorFor(m => m.MyCommaDelimitedProperty)
EDIT
I'll leave my previous answer because it could still be helpful in terms of being able to generate a control for a specific type of thing. You actually may still need to use it to get the right set up on your field to make the JS work properly.
However, when it comes to the client-side handling of this, I figured there had to be something out there already to solve this problem. (Never do more work than you have to.) A cursory search turned up a little script called Tokenfield for Bootstrap. I'm not sure if you're using Bootstrap or not. If not, I also found jQuery Tokeninput and jquery.token-field. I'm sure there's others, as well.
I'm writing my own Rule Engine, I've looked at a couple that existed but I'm looking for something else which I couldn't find examples to.
I'm looking for a similar application where I can dig into and learn how to do it.
Now, my question is REGARDLESS of the Rule Engine, more of a Form/Dynamic question, but if with your answer you can
relate to what I eventually want to do, that would be great.
Regarding the UI, I'm using Visual Form and the I'd like it to be like this:
http://i.imgur.com/5istREF.jpg
Now, once the user select on the final check box "And/Or" I want him to be able to enter another rule, exactly the same format as the first one.
http://i.imgur.com/N588sjj.jpg
Now the user can basically do it as many times as he wants, so I'm looking for a way to dynamically handle it and create buttons/pannels or even using the same ones (but every time he can enter different values).
Like I've said if you know any similar application/code that I can look into, regardless of rule engine, that will help as well.
Eventually I will take all the fields that he entered and turn it into code.
If I understand you correctly, what you can do is make a controller of your own which is defined in an additional form and then you can add it to your main form as much as you want.
You can define this new controller (meaning a new form) to hold only a single line of the comboBox and then add it to a location in your main form which is based on the location of the previous controller.
Here is an example which adds several control of a class called CNewControl to a tab called newControlsTab one after the other.
int controlHeight = 0;
foreach (CNewControl newControl in newControlList)
{
this.newControlsTab.Controls.Add(newControl );
newControl.Dock = DockStyle.Top;
newControl.Location = new System.Drawing.Point(40, 3 + controlHeight);
controlHeight += newControl .Size.Height;
}
You can of course change it to add your line only once when the user chooses the appropriate option in which a line should be added.
Background:
I am new to MVP and just coding my first winform application using Model View Presenter
Question:
I have been browsing for best practices on how to write user input validation code for windows controls (e.g TextBox etc) and where to put that code in winforms application using Model View Presenter desing pattern but still confused.
Let me explain
Suppose I have some TextBox controls on my form, which accept inputs like Name, Phone, email, zip etc. Normally I would call different methods like validateName(), validatePhone(), validateEmail() and validateZip() then in each of these methods I would definitely have to check that the input provided by the user in not empty like
if(txtName.Text.Length == 0)
{
errorMessage = "Name is required.";
return false;
}
if(txtEmail.Text.Length == 0)
{
errorMessage = "e-mail address is required.";
return false;
}
That smells like code repetition and I think there must be a better and efficient way to check whether the text is not null (may be by looping through all textbox controls).
So, What I am thinking is to have a CommonMethods class containing common methods like CheckifTextEmply(), CheckifNumber() etc and use this class throughout all my forms since these is common functionality and can be used by other TextBox controls on other forms in the project.
Now can you please tell me if
1. Is this the right approach, if not then how should I approach this issue
2. If right, where should I put the CommonMethods class (code) in Model View Presenter design.
Regards,
ZB
Looks a bit old post. Try creating a method which takes control as an argument and then try to validate it.
bool validate(TextBox txt)
{
return string.IsNUllOrEmpty(txt.Text);
}
you can also try taking a params[] argument to take multiple controls and validate them.
Regarding the error messages, instead of "Name is required" if you go for "required field" message, it will make the job easier. But if not, try creating dictionary of control and bool, pass false if the validation fails and take action according to it.
I know the answer is not very descriptive, but right now, I am a bit busy so cant take much time to explain this. Let me know if it helps.
I need to bind labels or items in a toolstrip to variables in Design Mode.
I don't use the buit-in resources not the settings, so the section Data is not useful. I am taking the values out from an XML that I map to a class.
I know there are many programs like:
http://www.jollans.com/tiki/tiki-index.php?page=MultilangVsNetQuickTourForms
but they work with compiled resx. I want to use not compiled XML.
I know that programatically i can do it, i create a method (for example, UpdateUI()), and there I assign the new values like this:
this.tsBtn.Text=Class.Texts.tsBtnText;
I would like something i could do from Design Mode or a more optimized way than the current one. Is there any Custom Control out there or Extension?
Aleksandar's response is one way to accomplish this, but in the long run it's going to be very time consuming and won't really provide much benefit. The bigger question that should be asked is why do you not want to use the tools and features built-in to .NET and Visual Studio or at least use a commercial third-party tool? It sounds like you are spending (have spent?) a lot of time to solve a problem that has already been solved.
Try with inheriting basic win controls and override OnPaint method. Example bellow is a button that has his text set on paint depending on value contained in his Tag property (let suppose that you will use Tag property to set the key that will be used to read matching resource). Then you can find some way to read all cache resource strings from xml files (e.g. fictional MyGlobalResources class.
public class LocalizedButton : Button
{
protected override void OnPaint(PaintEventArgs pevent)
{
base.OnPaint(pevent);
this.Text = MyGlobalResources.GetItem(this.Tag.ToString());
}
}
You can use satellite assemblies for localization and generate them using your XML file as a source for the translated entities.
more about satellites http://msdn.microsoft.com/en-us/library/21a15yht(VS.71).aspx
sure it's not from design mode, but there's no way to do it this way with your restrictions.
For a C# UserControl on Windows Mobile (though please answer if you know it for full Windows...it might work) how do you change what shows up in the Designer Properties window for one of the Control's public Properties. For example:
private Color blah = Color.Black;
public Color Blah
{
get { return this.blah; }
set { this.blah = value; }
}
This shows up for the control, but it's in the "Misc" category and has no description or default value. I've tried using the settings in System.ComponentModel like "DesignerCategory", such as:
[DesignerCategory("Custom")]
But says this is only valid for class declarations... could've sworn it was the System.ComponentModel items I used before...
Update:
#John said:
DesignerCatogy is used to say if the
class is a form, component etc.
Try this:
[Category("Custom")]
Is there a particular namespace I need to use in order to get those?
I've tried those exactly and the compiler doesn't recognize them.
In .NETCF all I seem to have available from System.ComponentModel is:
DataObject,
DataObjectMethod,
DefaultValue,
DesignerCategory,
DesignTimeVisible,
EditorBrowsable
The only one it doesn't scream at is EditorBrowsable
DesignerCategory is used to say if the class is a form, component etc.
For full windows the attribute you want is:
[System.ComponentModel.Category("Custom")]
and for the description you can use [System.ComponentModel.Description("This is the description")]
To use both together:
[System.ComponentModel.Category("Custom"),System.ComponentModel.Description("This is the description")]
However this is part of system.dll which may be different for windows mobile.
Is this of use to you? I am not into CF development, but it looks like you need to add some XML metadata to enable it:
http://blogs.msdn.com/bluecollar/archive/2007/02/08/adding-compact-framework-design-time-attributes-or-more-fun-with-textboxes.aspx
Interesting read.. Looks like a lot of design time support was stripped out of CF because you dont design them on the devices.. Which seems kinda weird to me.. Cant imagine using a handheld as a development rig!
Scroll down about half way for the good stuff ;)
The article does not suggest that anyone is designing ON the device. However, when you create a Compact Framework project, the compact framework (for your desktop PC) is used to handle design time rendering. If you think about it that is what you expect. The same framework (or nearly so) is used to do the rendering both on your PC at design time and later on the device at runtime. The issue is that the design time attributes were not added to the compact framework (I assume to reduce the size).