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It makes sense! Sorry for the confusion.
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Hello
I'm trying to figure out the best way to update TextBoxCell value on a Binded Datagridview
The values comes from a list of +/- 1000 allowed value
The Dgv is Binded to a datatable
I think that it will be too heavy and not necessary to create a ComBoBox column for that dgv
But I do not find many information about the use of a single Combobox cell to display "on the fly" when editing a TextBoxCell
Thank for any Help
N.B. : For now I'm using a ContextMenu with a ComBobox Item
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Even if you find a suitable way of showing a ComboBox 'on the fly' I suspect that the time taken to load the +/- 1000 options will be at least as great (as heavy), if not greater than the time taken when using a DataGridViewComboBoxColumn.
From this point of view I cannot see why you do not use a ComboBox column. Or is there some other reason?
Henry Minute
Do not read medical books! You could die of a misprint. - Mark Twain
Girl: (staring) "Why do you need an icy cucumber?"
“I want to report a fraud. The government is lying to us all.”
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Thank You Henry
To be honest I've very little experience about using ComboBox on a DataGridView
I know that it can be tricky and I don't really know when a ComboBoxCell is suitable instead of a ComboBoxColumn
But the constraints here are
- The DGV is Binded and normaly I use the AutoGenerate Column
- There is only ONE column editable in the DGV
- I want to see normal TextBox cell and make the Combo appears when a cell is edited
- There is only ONE List for the Combo
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A ComboBoxColumn is made up of ComboBoxCells so to get a ComboBoxCell all you have to do is set that Column to be a ComboBoxColumn.
Here[^] is a sample using a ComboBoxColumn, work through it and see if it is anywhere near your requirements.
Pretty much anything that can be done in code can be done through the designer for DataGridViews. Look here[^] for an example.
Henry Minute
Do not read medical books! You could die of a misprint. - Mark Twain
Girl: (staring) "Why do you need an icy cucumber?"
“I want to report a fraud. The government is lying to us all.”
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I have realized that I haven't answered your other points, I didn't really see them because I thought they were your sig. 
olibara wrote: - The DGV is Binded and normaly I use the AutoGenerate Column
Using the 'Data Sources Window' you can set individual database columns to use specific types of DataGridViewColumns. By expanding the tree so that you can see the column of interest, make sure that your form is selected in the designer, go back to Data Sources and select the the column. It should display as a combobox which will list the types of controls that can be used, select the combobox option and away you go. When you drag the DataSource onto your form it will make a grid with a comboboxcolumn.
olibara wrote:
- There is only ONE column editable in the DGV
- I want to see normal TextBox cell and make the Combo appears when a cell is edited
The ComboBoxColumn looks like a TextBoxColumn until you edit/select it.
olibara wrote: - There is only ONE List for the Combo
That is normal.
Henry Minute
Do not read medical books! You could die of a misprint. - Mark Twain
Girl: (staring) "Why do you need an icy cucumber?"
“I want to report a fraud. The government is lying to us all.”
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Thank you Henri
I'm sorry to reply so late but I did'nt get the notification of your reply
I will investigate because using the Combobox directly in the DGV is far better than my actual solution to set the ComboBox in a contextMenu
It is not easy to find good explaination about the different way to use a combobox in a datagridview
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Hi all,
I was wondering if there is a smooth way to accomplish the following:
Lets say I have a class that accepts delegates (or anonymous methods) that return strings.
Those refs are then stored.
I want to create an eventhandler that is fired when a result of such a delegate changes
(just like the TextChanged event of TextBox but maybe named: DelegateResultChanged)
I came up with a background thread that periodically calls the delegate and compares the result with the original result,
but that seems a little too much for archiving the desired result.
Any ideas on how this can be done "the right way"?
Any ideas are kindly appreciated
best regards
Andy
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If you are using binding, you might want to consider looking at INotifyPropertyChanged as shown here[^].
The funniest thing about this particular signature is that by the time you realise it doesn't say anything it's too late to stop reading it.
My latest tip/trick
Visit the Hindi forum here.
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Unfortunately I am unable to use binding for this one.
I deal with Control objects that do not provide the PropertyChanged event.
Anyway, thanks a lot for your contribution!!
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Well, the result changes when one or more of the inputs change, so what you really need to watch for is a change to the inputs. If this is on an object that implements change notification, you could pass that through and only check for a new result if the object reports a change.
But as for a changed event on the function itself... To my knowledge, no such thing exists. That function isn't going to re-run every time the inputs change, so the program doesn't even know what the new result is until you ask for it.
Off the top of my head, another alternative...
Instead of passing a function, wrap that up in a lightweight class:
public class FunctionWatcher
{
public FunctionWatcher(INotifyPropertyChanged caller, Delegate function)
{
}
private Delegate Callback;
public object Result { get; private set; }
public event EventHandler ResultChanged;
private void CallerPropertyChanged(...)
{
}
}
Again, this relies on having some object providing change notification... Otherwise your current solution might be the only one.
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That sounds pretty good.
The reason for dealing with this is to have some kind of watcher that is able to be fed with Control objects in order to tell if
something has changed in one control or a group of controls and saving is required.
So I am dealing with List<Control> where Control does not provide the PropertyChanged interface.
I already implemented TextChanged for those Control objects to raise the "SomethingHasChangedEvent".
So far everything works fine.
The delegate option is an addon for cases where something else has to be watched instead of a Control object.
Let's assume a function that checks some DataGrid fields or whatever, cases where I do not want to register a lot of Controls to get a TextChanged handler attached.
After thinking about this for a while I recognized that asking the watcher if it is "dirty" and going through the delegate list for checking this might be enough.
On the other hand, why not providing this event, it might become useful later... yeah, and I like events too 
The timer-idea just does not feel well... I have no idea how many work these delegates actually perform, so performance might become an issue later.
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Hmm... Well, if you can get them all to raise some sort of change event, then you can just subclass a wrapper for each type... One to watch a control for TextChanged, one to watch an object implementing INotifyPropertyChanged, etc etc. They could all, in turn, raise the same change event after checking the result.
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Good point Ian, I am just afraid that I am in a situation where I need to provide a fast and flexible solution... that's why I came up with the delegate stuff.
The people who wan't to use it can provide their own mechanism for resolving the original-value and the changed-value...
Just without an event...
I am really not sure if this event would be needed... maybe if some buttons will be disabled if changes have occured... but that's pretty much all I can think about.
I am not sure if I can implement INotifyPropertyChanged (I am used to work with this buddy in WPF - right now it's a WinForm app) on all circumstances...
Imagine a third party control that does not have a Text property or a TextChanged event.
Whatever this control is huge and does not implement INotifyPropertyChanged.
Right now I can pass a delegate to the watcher (it has AddControl(Control control) and AddDelegate(MyDelegate del) methods to add whatever is needed) and the one who uses the watcher can take care about whatever he thinks might be suitable to figure out if changes occured or not.
At that point I am unable to continue without subclassing something in order to bring the INotifyPropertyChanged into play.
I do not wan't the guyzos to change their objects or whatever... they should be able to implement it easily and without too much changes... on the other hand it is quite likely that the watcher will be heavily reused...
...where to go
What do you think?
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Well, if the control doesn't raise any useful events, your options are limited, and the timer solution is about all there is (Just make sure it's sleeping between checks, not calling continuously).
Maybe you could hide the complexity with private classes... I'm still in favor of the wrappers to merge all the different possibilities into a single event type... When you pass in the control, it'll check for a few common types (For a TextBox, it would look for TextChanged. For a checkbox, CheckedChanged. If it's an INotifyPropertyChanged, PropertyChanged). Depending on the type of control passed, it creates a different wrapper that hooks the necessary event and supplies a simple Changed event. If it can't find an event to hook, it falls back to the timer method...
public void MonitorObject(object obj, Delegate valueToMonitor)
{
if (obj is TextBox)
Add(new TextChangedWatcher(obj as TextBox, valueToMonitor));
else if ...
else
Add(new DefaultObjectWatcher(obj, valueToMonitor));
}
private class ObjectWatcher
{
public event EventHandler Changed;
private Delegate ResultCallback { get; set; }
private object PreviousValue { get; set; }
protected void OnCheckValue()
{
object newValue = ResultCallback.Invoke();
if (!object.Equals(PreviousValue, newValue))
{
PreviousValue = newValue;
if (Changed != null) Changed(this, EventArgs.Empty);
}
}
}
private class TextChangedWatcher : ObjectWatcher
{
public TextChangedWatcher(TextBox ctl)
{
}
}
private class CheckedChangedWatcher : ObjectWatcher
{
}
private class NotifyObjectWatcher : ObjectWatcher
{
}
private class DefaultObjectWatcher : ObjectWatcher
{
}
Anyway... The idea would be to hook events when possible, and only fall back to the timer when there are no known events to hook.
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Yes, you are right Ian.
I guess I'll go for the wrapper (I like wrappers anyway).
Maybe I'll replace the timer-part at a later time, but for now it'll suit my needs
Thank you Ian for your input, I really appreciate that,
best regards
Andy
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Why is dynamic polymorphism so called? Want to know why not how it is achieved !
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Here[^] are some reasons.
Just say 'NO' to evaluated arguments for diadic functions! Ash
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Oh!! Thats the bunch from which I selected one. 
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Most of the link gives how to achieve dynamic polymorphism. I dint get an accurate answer
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There's a fairly reasonable definition of dynamic polymorphism here[^].
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maB_J wrote: I dint get an accurate answer
What do you mean by accurate? Did you read the first link in the list I sent you? It gives a full definition of Dynamic Polymorphism; you could also go to Bjarne Stroustrup's web site and read everything he has to say about it.
Just say 'NO' to evaluated arguments for diadic functions! Ash
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hey guys..i try to add datas by stored procedure with 15 parameters..it works well..the problem is in my ProcessLayer..i have Firmalar class like below.
public class Firmalar
{
public string firma_adi { get; set; }
public string yetkili1 { get; set; }
public string gsm1 { get; set; }
public string email1 { get; set; }
public string yetkili2 { get; set; }
public string gsm2 { get; set; }
public string email2 { get; set; }
public string yetkili3 { get; set; }
public string gsm3 { get; set; }
public string email3 { get; set; }
public string telefon1 { get; set; }
public string telefon2 { get; set; }
public string telefon3 { get; set; }
public string telefon4 { get; set; }
public string telefon5 { get; set; }
}
and i try to add data in my processLayer like that
public void InsertFirm(Firmalar fir)
{
try
{
fir = new Firmalar();
cmmd = d.InsertData();
cmmd.Parameters.AddWithValue("@firmanin_adi", System.Data.SqlDbType.NVarChar).Value = fir.firma_adi;
cmmd.Parameters.AddWithValue("@yetkili1", System.Data.SqlDbType.NVarChar).Value = fir.yetkili1;
cmmd.Parameters.AddWithValue("@gsm_num1", System.Data.SqlDbType.NVarChar).Value = fir.gsm1;
cmmd.Parameters.AddWithValue("@e_mail1", System.Data.SqlDbType.NVarChar).Value = fir.email1;
cmmd.Parameters.AddWithValue("@yetkili2", System.Data.SqlDbType.NVarChar).Value = fir.yetkili2;
cmmd.Parameters.AddWithValue("@gsm_num2", System.Data.SqlDbType.NVarChar).Value = fir.gsm2;
cmmd.Parameters.AddWithValue("@e_mail2", System.Data.SqlDbType.NVarChar).Value = fir.email2;
cmmd.Parameters.AddWithValue("@yetkili3", System.Data.SqlDbType.NVarChar).Value = fir.yetkili3;
cmmd.Parameters.AddWithValue("@gsm_num3", System.Data.SqlDbType.NVarChar).Value = fir.gsm3;
cmmd.Parameters.AddWithValue("@e_mail3", System.Data.SqlDbType.NVarChar).Value = fir.email3;
cmmd.Parameters.AddWithValue("@tlfn1", System.Data.SqlDbType.NVarChar).Value = fir.telefon1;
cmmd.Parameters.AddWithValue("@tlfn2", System.Data.SqlDbType.NVarChar).Value = fir.telefon2;
cmmd.Parameters.AddWithValue("@tlfn3", System.Data.SqlDbType.NVarChar).Value = fir.telefon3;
cmmd.Parameters.AddWithValue("@tlfn4", System.Data.SqlDbType.NVarChar).Value = fir.telefon4;
cmmd.Parameters.AddWithValue("@tlfn5", System.Data.SqlDbType.NVarChar).Value = fir.telefon5;
cmmd.ExecuteNonQuery();
}
and inside of my form's code i try to send parameters...
private void btnEkle_Click(object sender, EventArgs e)
{
try
{
if (txtFirma_adi.Text.Length != 0)
{
firma = new Firmalar();
h.InsertFirm(firma);
firma.firma_adi = txtFirma_adi.Text;
firma.yetkili1 = txtYetkili_adi.Text;
firma.gsm1 = txtGsm.Text;
firma.email1 = txtEmail.Text;
firma.yetkili2 = txtYetkili2.Text;
firma.gsm2 = txtGsm2.Text;
firma.email2 = txtEmail2.Text;
firma.yetkili3 = txtTetkili3.Text;
firma.email3 = txtEmail3.Text;
firma.gsm3 = txtGsm3.Text;
firma.telefon1 = msktlf1.Text;
firma.telefon2 = mskTlf2.Text;
firma.telefon3 = mskTlf3.Text;
firma.telefon4 = msktlf4.Text;
firma.telefon5 = mskTlf5.Text;
}
}
}
but the values dont go to my stored procedure..and it gives error sp_AddDatas expects parameter @firmanin_adi...so how i can send the values to my stored procedure..
vemedya.com
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erdinc27 wrote: fir = new Firmalar();
Inside method InsertFirm(Firmalar fir) why are you again intializing Object? Use the received object itself.
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