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?
A 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:
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.
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.
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.
I;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
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?
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:
I 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
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?
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 ??
I 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?
Well 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..
I was writing a program for creation of form to ticket reservation. The form creation and everything is done a runtime. The problem is that i wanted to include a validation process in which the program will check whether user has entered the data(name) before showing select airline list box There are 2 if conditions which i both want to validate and if both the IFs are validated then i want it to show the list box.I dont know how to do that. Below is the code snippet
Private Sub button_selectair(ByVal sender As Object, ByVal e As System.EventArgs) If Me.Controls.Contains(t1) Then If (t1.Text.Length <= 3) Then MessageBox.Show("please enter a proper name")
In a DatagridView I have databound checkboxcolumns. But if I check or uncheck multiple checkboxes, not all changes are saved. (It doesn't trigger the property Set method on all, maybe on every 2nd). However if I after each checkbox-click, click on another cell (column) before the next checkbox, then all actions will trigger the Set methods. So it seems the cell validation does
i have a vb.net form button that go through a jquery validation before excude a function in the code behind , actually in either ways if the validation is true or false the function stopped and never call the vb.net function how can i make the it proceed to the code behind ?
vb.net form (textbox and button ) <asp:TextBox ID="ToCc" runat="server"></asp:TextBox> <asp:Button ID="emailSend" runat="server" Text="send" />
i need to restrict users selecting check boxes multiple times, only one check box should be seleted in my asp.net form ,i am not using a checkbox list.
I have a form where the user is to enter the beginning odometer value and ending odometer value. I have the code correct to check and see if there is a numerical value entered into to each text box. When the user enters the ending odometer value and that value is less than the beginning odometer value I want an error provider to stop the user from tabbing to the next field and let the user know that the ending odometer value cannot be less than the beginning odometer value.how to set this up. I have some code in there that doesn't seem to be doing the job for me.
Private Sub BeginOdometerTextBox_Validating(ByVal sender As Object, ByVal e As System.ComponentModel.CancelEventArgs) Handles BeginOdometerTextBox.Validating 'test beginning odometer for numeric value[code]....
I have a theory that the variable for the beginning odometer value is working in the ending odometer value block of code. Not really sure about that though.
In my spare time i give myself programming stuff to do. Today i want to write a function that goes through a string, if the string contains any numeric value the function must return false, if the string has any special characters it must also return false else return true. For example the following strings would return as follows:
My company uses control numbers to keep track of all of our inventory for every product that is entered into our warehouse.(ex.G123456789, T987654321) 1st Alphabet followed by 9 digits of numbers.Most of the time, these control numbers are scanned into the system by using a barcode scanner but some times these control number are entered into the system manually by hand.People make mistakes and sometimes enter in different control number.i want to be able to code my vb so that when the control number does not meet the critarion then program displays an error message.So i want to check for the first character which needs to be an alphabet and characters 2-10 to be a number.