I tried binding data to combobox at the runtime in the form load event. I had written the following bind function,
Private Sub BindComboBox()
Dim da As SqlDataAdapter
Dim conn As SqlConnection
Dim ds As DataSet = Nothing
[code]....
The problem is cboSubject.SelectedText is returning empty string.
My combobox (Me.cbHomeDrive) doesn't get properly initialized if I use Me.cbHomeDrive.SelectedText = "E:" On Form_Load:
For i As Integer = AscW("C"c) To AscW("Z"c) Step 1
Me.cbHomeDrive.Items.Add(New ComboBoxItem(ChrW(i) + ":"))
Next
Me.cbHomeDrive.SelectedIndex = 26 - 3
[code].....
Then it sets the correct selected item (E:).Why does it not work with Me.cbHomeDrive.SelectedText = "E:"?
I have some code which gets child items for a menu via the GetChildren function which takes a list of menuData: Dim builtMenu As New List(Of MenuData)(_rawData.FindAll(Function(item) item.GroupingID = 0))
For Each menuData As MenuData In builtMenu
If menuData.Children IsNot Nothing Then
menuData.Children.AddRange(GetChildren(menuData))
End If
Next
If I check if menudata.children isnot nothing, it always is nothing because the GetChildren function is yet to run (providing the child items, which do exist). If I remove this check and just have this code:
Dim builtMenu As New List(Of MenuData)(_rawData.FindAll(Function(item) item.GroupingID = 0))
For Each menuData As MenuData In builtMenu
menuData.Children.AddRange(GetChildren(menuData))
Next
Then I am presented with a Object reference not set to an instance of an object error on menuData.Children.AddRange(GetChildren(menuData))
I have a WPF application that uses a third-party library to perform a specific task; this library, in one of its methods, executes the statement Assembly.GetEntryAssembly(). If I run the WPF application on debug (by running a .Net exe for testing) the library works properly and Assembly.GetEntryAssembly() returns a reference to the assembly of the executable, but in production I have a different situation that causes me some problems.
[Code]....
I have the following code in my application. When it is executed it brings out a null value at times, where i am sure there should be a value returned. I have checked by running the sql statement in the database and it returns the correct value. What could be wrong with my code? [Code]
View 6 RepliesRather interesting bit on this one, I have all the code where it should be working but whenever it hits parse1 it returns the file as null. [code] I probably just need a fresh pair of eyes because I'm not seeing where this is glitching (...or if it's just my computer in this case.)Rather annoying at this point, tried break points and following the execution to catch the error but no such luck.
View 2 RepliesI have some VB.NET code that creates a TransactionScope instance:
LoggingUtility.LogDebug("UpdateCallTable", "SatComCallDataImporter", "About to associate call data with contracts")
Using ts = New TransactionScope()
LoggingUtility.LogDebug("UpdateCallTable", "SatComCallDataImporter", "Getting all unimported SatCom calls")
My application is throwing an exception on the call to the creation of a new TransactionScope, with "Object reference not set to an instance of an object.". The exception isn't thrown on my development machine or my test machine; only on the customers production machine, and I have no idea why. I've placed debug lines immediately before and after this line so I'm positive it is this line causing the problem.
A have used TransactionScopes throughout the application and this is the only place throwing the exception on the client machine."About to associate call data with contracts" gets written to the log and the next log entry is the "Object reference not set to an instance of an object".
Code works fine if I move it out of a transaction.I've been struggling with this for 4 days now and have got no closer.
i hav two openfilefialogs(1 and 2). So i also have a listbox. the files opened with the openfiledialogs will be added to the listbox. and when i need to open the files i need to see if they are from which openfiledialog. so
it is like this.
Path.GetDirectoryName(OpenFileDialog1.FileName) & "" & Form3.ListBox1.SelectedItem.ToString
'if this returns a null then go to this
Path.GetDirectoryName(OpenFileDialog2.FileName) & "" & Form3.ListBox1.SelectedItem.ToString
Is their a more elegant way to assign a space to a value, if a database call returns null for a data set column? I am doing the following check which is pretty tedious:
If (ds.Tables("employee").Rows(0).Item("txtNamePrefix").IsDBNull(0)) Then
txtNamePrefix.Text = ""
Else
txtNamePrefix.Text = ds.Tables("employee").Rows(0).Item("txtNamePrefix")
End If
I have a DataGridView connected to a DataSet. I want to allow the user to update and insert new records on the RowLeave and CellLeave events. The Update method works:
Me.ExpensesTableAdapter.Update(Me.DataSet1.Expenses)
I am basically trying to access the CLSID portion of the registry... some CLSIDs are working, some arent...
Here is my code:
Dim regkey As RegistryKey
regkey = Registry.ClassesRoot.OpenSubKey("CLSID" & location & "InprocServer32", False) 'Just Returns null when im looking for a certain CLSID
Dim SubKeyvalues() As String = regkey.GetValueNames()
Dim subkeyvalue As String
subkeyvalue = regkey.GetValue(SubKeyvalues(0))
I'm converting a system of numerous programs from foxpro/foxweb/javascript to asp.net/vb/sql server.
I'm coding for a dropdownlist which is currently controlled via js.
I don't like using the control this particular way, but I want to maintain look and feel for the customer.
The control is initialized with some values via Page_Load() in behind code.[code]...
I'm trying to get data with the methods below and I get null response and can't figure out why. I'm just trying out a different way of using a wcf service from silverlight and I don't understand something that I should.[code]...
The employee object will stay null. If I put a break into the service call and follow through the code it finds the correct record from the database and the return statement shows an object with the correct data but still the employee object in silverlight side will remain null.
[Code]...
By my logic, this should only assign .length to index IF the length of strItem is longer than 0. This check is there in case the listbox is empty, or the user has not selected an item. However, everytime I go through this code without an item selected I get:
[Code]...
I have a several form elements that I am dynamically creating with javascript when a user changes a number value in a textbox, by filling the innerHTML of a div like so:
dfinnerhtml = dfinnerhtml + "<div class='field'> ";
dfinnerhtml = dfinnerhtml + "<textarea name='textbox1" + suffix + "' type='text' id='textbox1" + suffix + "' value='' rows='4' cols='20' class='field'></textarea> ";
dfinnerhtml = dfinnerhtml + "</div> ";
Then, in the aspx.vb code behind, when the user clicks the Save button, I run through a series of Requests to try and add the values that are in these form elements to a SQL string:
Dim DFTestValue1 As String DFTestValue1 = Request("textbox" & c.ToString)
where c is a loop counter to the # of textboxes created (the input value mentioned above that triggers the create) The problem here is that this code works in Internet Explorer but not in Firefox or Chrome. The Request() value returns null and nothing is saved. I hope I've explained this well enough.
I have a vb.net app that I can read a .xls file into a dataset or loop through as oledbdatareader and it gives the same result.Some of the rows have all nulls when I loop through them but if I open the same file in Microsoft Excel I can see that row fine.[code]From the info above the first two SKU values would come through fine but when I get to the 3rd row it would show a null.Is it possible that it kind of inherits the first rows type and since the 3rd row isn't all numeric if nulls it? [code]
View 1 RepliesI have a select statement which was returning the required values but when I changed the OS date from English(US) to English(UK), it now returns null. I believe the problem is concerned with date since in the query am selecting values where the date from the database is the same as the date in a combobox but I don't know what else I can do. It almost looks like the dates in the combox and in the database are not the same and yet the date in the combobox is actually retrieved from the database and has been returning values fine until I changed the system date format.Here's my select command:
cmd4.CommandText = _
"SELECT sum(brought_qtty), recieved_qtty from brought_coffee, centre_weigh where brought_date=#" & _
dtComb.Text.Trim & "#" & _[code].......
how can i capture system wide selectedtext?
i've managed so far to get a global mousehook + i'm hoping to capture the selectedtext from anywhere system wide when the user left clicks.
i tried using the keybd_event api to send CTRL+C to copy any selectedtext to the clipboard but it has unexpected effects + seems to run before the text i've just selected becomes selected.
here's the code i'm using:
Public Class Form1
Private Declare Function keybd_event Lib "user32" Alias "keybd_event" _
(ByVal bVk As Byte, ByVal bScan As Byte, ByVal dwFlags As Integer, _
[Code].....
I am using vb.net sqlite.net and dblinq0.20.1 to search a sqlite table on a primary key field.My code looks like this
Dim blb = (From d In db.Data Where d.UID = myuid Select d).Single
This returns the error "Coalesce used with type that cannot be null" .If I search on a nullable field it works fine.
I am making use of a 3rd party dll and am encountering some strange behavior in VB, which doesn't occur in C# Perhaps someone can explain what is going on. Anyhow, I am making use of a method in this 3rd party library which accepts an array parameter ByRef. The end result is the variable should remain null after the method call, but it is returning initialized for some reason.
[Code]...
Code:
Application.DoEvents()
Error:
[code].....
I have two combobox on which will display company and department names. There is a"SelectedIndexChanged" event for company combobox. I don not want that is triggered when value of combobox are empty or null. I tried CompanyCombobox.seletedValue is not null and other ways, but they were not working. How do I detect there is empty or null value on combobox?
View 3 RepliesThis same (Identical ) code works well in another program but does not in windows service... Returns 0 for window handle ...?
Public WindowStr As String = "ImagSrvWindow"
Protected Overrides Sub OnStart(ByVal args() As String)
'necessary to get control to paint Pic&Txt boxes in stream of Browser navs
[Code].....
I'm trying to show all window titles including the corresponding icons, much like Windows Task Manager does. This works only to a certain extent though - although I am able to get the windows' title bar texts, the icon is not always available.
For getting the icon I pass the WM_GETICON message to SendMessage (source):
Public Const WM_GETICON As UInteger = &H7F
Public Function GetWindowIcon(ByVal WindowHandle As IntPtr) As Icon
Dim IconHandle As IntPtr = SendMessage(WindowHandle, WM_GETICON, 0, 0)
[Code].....
For some windows, this returns just the correct icon. For others, it returns Nothing since IconHandle is equal to 0. In Windows Task Manager and on the taskbar they show up just fine.
the combox is bound database table,but it is not displaying the contents of table in database,instead it is displaying corresponding null values(blank).it is showing just "select" and the blank spaces corresponding to the number of items in database
here is my
Function combobfill() As DataSet
addconnection.Open()
Dim selectstring As String = "select materialsname from materialtype_table"
[Code]....
I'm using vb.net and sql server 2000 for developing my application....The problem i'm having is the Null Reference Exception on the Following line of code:
Dim cmd5 As New SqlCommand("select crtns_removed, pieces_removed, scheme from Outgoing_Invoice where invoice_no = '" & Me.ComboBox5.SelectedItem.ToString.Trim & "' And category = '" & Me.ComboBox1.SelectedItem.ToString.Trim & "' and item_name = '" &
[code].....
I have a combobox with a dropdownstyle of dropdownlist (style 2). When a user finishes making entries and clears the form, I want the display value of this to return to null. With an unrestricted combobox, I could just set .text="" and be good to go; that doesn't work with the ones that are restricted.
View 3 RepliesI had added the items
1
2
3 to the combobox.
Then I gave the "Select" to the text of the combobox.
How can I able to reset combobox to select the text("Select").
I had tried by giving -1 to the SelectedIndex. But it gives only Empty.
This is for VB.NET Windows Application
I have given an Image for your reference
Image path for the reference [URL]
I had added the items 1 2 3 to the combobox.
Then I gave the "Select" to the text of the combobox.
How can I able to reset combobox to select the text("Select").
I had tried by giving -1 to the SelectedIndex. But it gives only Empty.
This is for VB.NET Windows Application
I've created a custom MessageBox (a Form), that has buttons Yes and No. There is a function popUp() to show the MessageBox. I would call the MsgBox in a parent as follows:
CustomMessageBox.popUp()
Now I want the message box to return a value:
Dim a as Intger = CustomMessageBox.popUp()
But this should only return once the user clicks a button in the message box.
My popup sub:
Dim thread As New Threading.Thread(AddressOf GetResult)
Public Function PopUp(Optional ByVal ErrorMessage As String = "", Optional ByVal Title As String = "", Optional ByVal ButtonType As ButtonType = ButtonType.OK, Optional ByVal MessageType As MessageType = MessageType.None)
[Code] .....
gotResult is a Boolean = false. It the user clicks a button gotResult is changed to true.
result is a integer containing the number of the button clicked.
When I run this code, the result is returned, even if the user doesn't click a button. I understand why, because the main thread of the form is not "paused" while the user has not clicked a button. How can I pause the message box itself, until a button was clicked?
I've tried this:
Public Function PopUp(Optional ByVal ErrorMessage As String = "", Optional ByVal Title As String = "", Optional ByVal ButtonType As ButtonType = ButtonType.OK, Optional ByVal MessageType As MessageType = MessageType.None)
[Code] .....
But now the whole message box is captured in a loop and the message box is like disabled, because it waits for the loop to end, so the user can't click anything.