I'm new to programming and am trying to learn how to developed data driven application and was wondering which method is recommended? I know there are some debates out there but most of the books I have recommend using object binding, but it doesn't offer any concrete information on how to implement it. I went to MSDN and most, if not all, the documentations are on dataset. So I guess my questions is, object vs dataset, which do you use?
I'm still trying to understand and use Use Cases and Test Driven Development, but having a hard time crossing the line. I'm hoping someone can provide a good example of how setting a datasource and/or databinding a gridview could be accomplished using Test Driven Development. Here is my pseudo approach at it.
I use objectbinding to display client data in a datagridview. The datagridview also contains a counry-column allowing the user to choose the country of the client.Unfortunately, databinding of comboboxcolumn does not seem to work if an own business class is used. Using a simple collection instead works well.Copy the sample code into a new windows project and the programm runs fine. Then comment and uncomment the two lines with "XXX" and the code will fail. Why and does anybody know how to make the sample code work by using the business object class(variable named "newClientListVariable" in the sample)? [code]
I have a form with a binding navigator on it. It also has a DGV and text boxes bound by the binding navigator. Everything works fine. If you scroll through the row's in the binding navigator it updates the DGV and text boxes at the same time. And also if you click any row in the DGV it automatically updates the text boxes.
Ideally I want to impletment some validation to make sure the users are not only filling in all the required text boxes but also that the data entered is correct.
I have some validation setup in SQL, for example not allowing nulls on particular columns but I really need to be more extensive in the validation than that.
Ideally I need some way of validating the current row selected whether it's an existing row or a new one, before moving to the next row or before save is clicked on the binding navigator. Firstly because the SQL validation messages are not very good, secondly because whilst the data may meet SQL's requirments, it may not be right. For example SQL might accept 12:00 as a time but the program specification requires the user to input within a certain time frame, i.e. 14:00 - 16:00.
Finally, I feel like the validation needs to be handled immediatly on the record that is displayed as ultimatley, the way the form is setup, allows the user to add and amend more than one record at once and if the validation was handled on 4 or 5 different rows then it would bring another problem of having to bring each row up to correct. Therefore I think the best aproach is to handle each row before allowing the user to move onto another one.
I want to bind a column of a strongly typed dataset to a combobox. But the problem is i have to get only the distinct values from the column and also when a user inserts a value into that column the new value should be showned in the combobox at the same time.And also i want to make the first row of the combobox to be unselectable..[code]how to make this column distinct values
I have text box which I use the properties window, datasource set to bindigsource1 in my dataset.. I want to trim the text that is being populated.. Is there a wayt o do this through the visual studio gui or is it redo in codebehind?
I need to add rows to a DataSet using databound controls in VB.net. I've set up the data bindings themselves, they're bound the the correct controls, and the BindingSource uses the correct DataSet. The DataSet is filled from the DataAdapter correctly, and the binding source works, as the navigation controls all work fine. How do I use the controls to add new data to the DataSet? I guess there must be some kind of end-edit involved which would enable me to insert, update and delete records in the DataSet (as you would use with DataGridViews)
I have a typed dataset with 2 tables and a relation between the 2 tables. The relation is a 1 to 1 relation.First, who cane help me how to bind both the fields of the parent and the child table to a textbox.And second, in the dataset designer you cane preview the data. There a see for each record 1 row with all fields of the parent and also the fields of the child table. How cane i have the same result in a datagridview?
I have a manually created a dataset (dsPickingList) that I add data too as the user inputs data on a form. There is a datagridview on my form of which it's datasource is set to dsPickingList.What I would like to do is spot if a user deleteds a row from the datagridview and update the dataset (dsPickingList) as it is ultimatly this dataset that is stored to the db and printed, not the DataGridView.[code]This is why I need the action from the DataGridView to update the dataset
I have a simple form (textbox) bound to a dataview which includes a date. I bind the date column using TextBox5.DataBindings.Add("Text", dvCampaigns, "CamBdate")Doing so shows the results as '1/1/2011 12:00:00AM'. I want the time to not show with this date. I can reformat the date using the TextChanged method of the text box and I can live with that if I cannot find a more efficient way. Is there a way to format the date upon binding in the above line of code? Also where can I find a listing of all the allowable properties for binding statement above? Intellisense implies that there are more then just the "Text" property but I cannot find them in BOL or MSDN. My thought is that there might be a property to do this in one step rather than reformatting it.
I have a problem binding a radiobuttongroup to a dataset/datasetbindingsource. I have a field - among many others - in the dataset, holding int values 1-6 All fields are shown in textboxes on the windows form. But how do I make the radiobuttongroup show the value of the int field. value=2 => radiobutton2 is selected
The table field [recordaddeddate] is a Date/Time field in my Access database. Usually this field contains a date + time value. For filtering on my datagridview I want to filter on the date portion only. However the following genterates a 'The expression contains an unidentified function call DateValue' error. How can I filter on just the date?
My another question is in txtlani textbox I have to enter only digit i.e. 0 to 9 and currency formate i.e. 1,000.00 and 1,00,000.00 it is possible in text box.and another text box which I have to enter only date i.e. at run time in the text box show dd/mm/yyyy formate and I have to enter by user to enter date not to be left blank i.e. how it will show in the back end not null in MS access on both the text box?
If I declare my object at the beggining of my page class, and instantiate it in a dropdownlist selected_index change event. Shouldn't this object be available thru out the entire page and also persist thru a postback? I lose the object in my selected date change event in my calendar.
I'm trying to set the format of a column in a datagridview.When I put the format statement in the on load event for the form, it has no effect. When I put it in the cellformatting event I get the "Object reference not set to an instance of an object" error. I checked the column name. What I am doing wrong?
This is the code:Private Sub MeetingTblDataGridView_CellFormatting(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellFormattingEventArgs) Handles MeetingTblDataGridView.CellFormatting Me.MeetingTblDataGridView.Columns("Starttime").DefaultCellStyle.Format = "HH:mm:ss" End Sub What I'm trying to do is get rid of the date part of a Date/Time field (stored in an Access database) in a datagridview column.
Can you please explain me and/or show some good tutorials how to do it?It seems pretty complicated because visual studio usually does it all for you and that made me stupid and not to do anything about it.Things I don't know to do in code but I know VS does it for me:
[Code]...
I'm sure there is a good tutorial somewhere on the internet. I'm okay with doing it with designer, but now when I have a situation where I can't use MDI container but tabcontrol.Other solution would be to make a MDI container out of tabcontrol. Is it posible or only other form can be MDI container.
While I am running the project the cursor is blinking in the first name textbox then i am press the tab button then it is move to middle name textbox and then lastname and company name but when I am press after company name then it will jump to the button I want to jump the tab into Lani in Rs which is the next to company name textbox and then it will jump to Enter date.
I am having problem in the Enter Date field in the back end in the MS access I have already set the date in the back end i.e. short Date so, how to Formate the textbox in the front end i.e. in vb.net 2005
I'm using date in the format dd-mm-yyyy and I need to convert a string inthis format to a date type.My string is "18-01-2010" but when I do the conversion using dim TargetDate as date=CDate(TgDstr).where TgDstr is "18-01-2010", the resutant TargetDate, as note in the debugger window, is #1/18/2010# rather than #18/1/2010# which I expected.What change in code should I made to get the desired result?
(P.s. I've checked the current culture with the following line of code:
Dim str As String = CultureInfo.CurrentCulture.Name and get the result 'zh-HK'... and the date-time format I find in the control panel is also in dd-mm-yy format)
I have this piece of code that works very well and gives me the path the user's start menu:[code]This obviously uses late binding. Now say I want to do this in C#, or in VB.NET strict mode, neither of which support this kind of syntax with late binding.
Now I can change the TextBoxes or the object: MyObject.Two = 3 ..the object and TextBoxes are updated in two ways. Now I want to update the whole object: MyObject = New TestClass(3, 4) ...but this doesn't update the TextBoxes.
Is is possible to bind two BindingList<> object to the DataGridView? Both the bindinglist objects are of the same type. I tried binding an array of BindingLit<> object to the grid, but this fails.
I have created a user control in wpf which consists of a textbox and a listview. Now, I want to bind a class object to the list view from the form where I will use this control. So, basically I want to dynamically set the binding for the listview.
I have a problem about button click event and data binding.I have described my problem in the mark as following
Public Class Window1 Private Sub Window_Loaded(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs) Handles MyBase.Loaded Dim list_of_name As New List(Of String) list_of_name.Add("John")
Is it possible to bind a button to an object? I have a situation where I create lots of buttons dynamically and add them to a form, each button corresponds to a record in a database table, I want the button to hold all the info in the record without the need to search for the data each time I press it. I've already have the info in the tag property as a delimited string, but the process of extracting the info from the string is not efficient. if I add one new value I have to add the code to extract that info using string manipulation. I would rather have an object that represents the record so I can access each value directly.
am using VS 2005 and VB. However, if I am not using binding navigator, how can I manage the state of an object it is "added" ( or even "deleted") the property setter is only setting the state to "modified". where should i set it to "added" if i were to insert a new object to a database
I've read (or the only book that covers ado 3.5) is Murach ADO 3.5 and throughout the book, the author recommends using object binding so that's what I've been doing. However, I had a chance to look at all the codes for our applications at work, and only datatables are used.Was curious as to the difference/pros and cons between binding to an object, and binding to a table. I guess my real question is which one should I be using, datatable or object binding? Is there a definite answer or does it depends on the situation and what I want to do?
