I have two problems related to validation of the DGV cell. First; when I clicked a ToolStripButton, CellValidating event isn't fired. And then it causes problems for me. It needed to be validated.
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I'm translating the C# code found here [URL] to VB.net. Most of it I'm OK with, but the statement above has me stumped.
View 3 RepliesSome of my DataGridViewCells return the wrong value in their GetClipboardContent method. They are cells in a DataGridViewComboBoxColumn cells, so they use the displayed property, not the value property of the cell. I want it to return the value itself.An initial attempt was simply using
Protected Overrides Function GetClipboardContent(ByVal rowIndex As Integer, ByVal firstCell As Boolean, ByVal lastCell As Boolean, ByVal inFirstRow As Boolean, ByVal inLastRow As Boolean, ByVal format As String) As Object Return Value End Function in my DataGridViewComboBoxCell descendant but then I noted that this method is called more than one time per cell value, once for every data format DataGridView supports by standard, which are format="HTML", "Text", "UnicodeText" and "Csv". For csv, the base implementation appends a comma if it's not the last cell, for html it adds the correct tags depending on if it's the first/last row/cell in the table/table row, etc. I consider this format-specific, not cell-value specific.
So how could I replace the value that ends up in the clipboard without re-implementing all those format-specific aspects? That would result in quite some code for functionality that already exists in the base class, wouldn't it?
How to test for DataGridViewCell.Value with Option Strict On?
If DataGridViewCell.Value = "some value" then
Gives the error:
Option Strict On disallows operands of type Object for operator '='. Use the 'Is' operator to test for object identity.
EDIT:
The Solution is:
If DataGridViewCell.Value.ToString = "some value" then
I'm creating a new windows form application based on an existing AS400 application (don't ask).Now the users are used to have a fat, white, blinking caret all over the place, so the first thing they mentioned when they saw my initial release was "where did the cursor go?" "We don't know which field we're filling in"
I tried to explain that there is in fact a cursor inside the textboxes (and that it is called a caret), but they want their big, fat cursor back.After some searching on the internet, combining snippets, I managed to make the caret look like I want (in fact you can use any bitmap image as a caret as long as you invert the colours).Now this seems to work like a charm for textboxes but they want the same caret when they edit a cell of a datagridview (who could have guessed)
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[url]
I tried out this calendar column from msdn... I was fascinated by it and try to imitate it but now I want to use a simple usercontrol(a button and a textbox)
It is working fine but I have a bit of a problem with the look. it doesn't resize the cell
Just finished this and figured I would share.. It just uses images, but works very well.. Have a couple work arounds in there so you can still bind it to a Class. Let me know what you think:
View 1 Repliesi had a problem with datagrid view iam maintaining a visiting details of the patient in the datagridview containing the columns Visitingdate ..etc. my problem is how to insert a date control in the first cell in the datagridview. and that is to be done when user click on the cell. i didnt find any datagridviewdatecolumn in the datagridview properties . Is there any methods to display date control display at the time of cell click event
View 2 RepliesDataGridViewRow.IsNewRow property is set for the bottom (empty) row. If I set a cell value in the bottom row using DataGridViewCell.Value, IsNewRow remains set. What is the correct way to programatically set a cell value in the botton row to clear IsNewRow?
View 4 RepliesIn VB .Net 3.5, is it possible to change the color of a DataGridViewCell (unbound) to a different color and have the cell visibly change before losing focus or leaving the cell? I have a timer that's running that queries with the data present and I'd like for the colors to change immediately instead of after the user leaves the cell.
I've tried DataGridView.Refresh and Me.Refresh and don't get results.
What am I doing wrong? (Below is the code I use to change the background)
''' <summary>
''' Sets or clears the passed cells background to Red
''' </summary>
[Code]....
I wrote the following code in vb.net:-
cmdOnClick.CommandText = "SELECT * FROM patients where ID=" & grdPatients.Item(grdPatients.CurrentCell.ColumnIndex, grdPatients.CurrentCell.RowIndex)
it shows the error operator "&" is not defined for types "Strings" and system.windows.forms.datagridviewcell
When trying to validate controls on a windows form I realise the .validated() for each controls fires when the focus is lost. Instead I'd like to validate only when the button is pressed at the bottom, how would I do this?
View 3 RepliesA Form has two textboxes (txtA, txtB) both with the Causesvalidation property set to True. An ErrorProvider EP is added to the form.The Validating event is as follows:
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I have a form set up where users can enter their booking for a room at my college. I want to validate the user input to avoid SQL injection (my program uses a MS Access database) and also stop numbers and synbols in their name, etc.I can do the validation fine, but there is to be a lot of validation and then methods executed only if all validation tests come back as true. I did have something like this:
If txtName.Text = "" Then
frmBookErr.SetError(txtName, "Name field cannot be left blank.")
fail = 1
Else
[code]....
And then check the fail variable, but it obviously gets overridden later in the form if one of the validation tests come back as true.
Where to add this validation, or if there is a more efficient way of doing it and where to put it?
CODE:
I'm a non developer user of VB. I'm using a simple form to input data to a database. have some text boxes bound to data and use a Binding navigator. I want to be able to handle or catch the error when a non unique ID is added. I have tried to include an error handler in several places but the exception is generated anyway. For example I select to add a new record the change the id to a duplicate value and navigate to the previous record and get the error. I want to check or validate the value before it generates the error to avoid the program crashing if someone includes a duplicate id.
View 5 RepliesI;m making an application (who ins't xD), anyways, I'm using some encapsulation objects to transport stuff to the BLL. i was wondering (and might be sound stupid, I know) what you guys think is better practice:Either use Objects for transporting lots of stuff (like a BLL object to transport all its attributes) Or-handle around Strings through the GUI and only create objects when strictly needed.
Another question that just popped my mind: I'm using a Validation class in the BLL in order to validate stuff like "This particular object is already mapped, error" or "This is not well formed", and throw exceptions, instead of boolean values, since I'm at BLL level. Do you guys use a Validation class or perform the validation from the object itself? The old "who's responsible" problem.
I have decided to add some validation to my combobox, what I'm trying to achieve is to make sure that the user can ONLY enter fields that are in the combobox but the problem I have now is that if the user clicks on the combobox and doesnt enter anything and tries to leave the combobox the message box appears.
Private Sub Combobox1_Validating(sender As Object, e As System.ComponentModel.CancelEventArgs) Handles Combobox1.Validating
If Combobox1.Items.Contains(Combobox1.Text) = False Then
e.Cancel = True
[Code] .....
As stated before the coding does work, but I was trying to make sure the message box does not appear if the user doesnt enter anything in the combobox.
I have a form which imports a CSV into a datagrid. I have validation for new row, which has error provider appear on form. How can I add validation to the datagrid once the CSV has been loaded to flag that a certain cell must be completed for saving. I can do it in my dataset for new rows:-
Partial Class ContactsDataSet
Partial Class ContactsDataTable
Private Sub CheckContactName(ByVal contactsRow As ContactsDataSet.ContactsRow)
If contactsRow.IsNull("Name") OrElse contactsRow.Name = "" Then
contactsRow.SetColumnError(Me.NameColumn, "Must be completed")
[Code] .....
How can I do it for existing rows or imported rows or get error provider to appear on every cell (called Name) that is empty?
i`m totally new to vb actually.now using vb express 2008.i`m currently trying to create log in function.basically, i`m already create database (database in vb 2008 itself) for login,which the login table contain 3 columns, Username, Password and Designation.example
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Newbie question. I'm writing an ASP.Net MVC app in VB.Net and have been using NerdDinner as a sample (which is in C#). I'm stuck on the validation process specifically the code found in ModelsDinner.cs . I have tried converting it to VB.Net using [URL]...tools/convert/csharp-to-vb/ but it chokes on the Yield statement which found in the GetRuleViolations method (see code below). So my question is how would you do the equivalent in VB.Net?
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I have a problem in the validation of NumericUpDown control in VB.net. I want it to accept only the numbers, but it is accepting punctuations like '.' and apostrophe also, here my code what I did below, but still the problem persists, I used keypress:
View 4 RepliesI had used this code to validate email id in textbox,but it is not working properly?
Dim Expression As New System.Text.RegularExpressions.Regex("^[a-zA-Z][w.-]*[a-zA-Z0-9]@[a-zA-Z0-9][w.-]*[a-zA-Z0-9].[a-zA-Z][a-zA-Z.]*[a-zA-Z]$")
If Expression.IsMatch(Textbox1.Text) Then
MsgBox("The email address is valid.")
Else
[code]....
I have a textbox which has some text on it and when the user will click on it,The problem is, as there is already a text on the textbox when the user will click will diappear to type his respective text, the program is saving the text written also. How to prevent that? All I want is to prevent the program saving a blank textbox and the text written on it?
View 4 RepliesPrivateSubtxtMchNoForFile_KeyPress(ByValsender
AsSystem.Object, ByVale
AsSystem.Windows.Forms.KeyPressEventArgs)
HandlestxtMchNoForFile.KeyPress
[Code]...
I am trying to validate a textbox by checking the ASCII values on PreviewKeyDown event of the textbox.This method woorked fine with WinForms using vb.NET.The problem comes wen I use it in WPF.Is there a better method of carrying out validation of textbox in WPF forms ??
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how to validate an emailid
View 1 RepliesI have a newbie question hopefully the more experienced vb heads will be able to help me with, I have a command button which works like the following [code] I was thinking would it be possible to only run 'Code 4 if the messagebox.show has not appeared for Code 1, Code 2 and Code3?
View 1 RepliesWell im working agains a webservice that has a certificate that is not 100% correctly setup the certificate is setup for the domain [URL] and the api is located at [URL] now i cant connect to this webservice as i then get a WebException "Could Not establish trush relationship for the SSL/TLS secure channel. The remote certificate is invalid according to the validation procedure. Now my question is there any way to bypass this check i use a normal Web Reference (2.0) not a Service Reference..
View 5 RepliesThis video shows how to add validation for a textbox:[URL]..what about date ? I can't make it work for date.
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