I have searched and searched and searched enough until my Head aches! What I am trying to do is take an ATOM feed from here: National Weather Service Alerts and incorporate it into my program, however, I don't even KNOW where to begin :( What I want to do eventually is download the Atom feed and place it in a scrolling label. I don't want to parse it pulling out sections or anything. Just want to display the NWS alert for my area. I don't expect anyone to just write out the code or anything, but any help pointing me in the right direction for programming it simply and painlessly for an intermediate vb programmer would be greatly appreciated. Please Help!
Here is a code sample that should work for your case. Assuming you already downloaded your Atom feed and saved it to your disk. If not, you may need a slight modification:
Imports System.Xml
Imports System.ServiceModel.Syndication
Public Class Form1
Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
Dim messageList As New Generic.List(Of String)
Using feedReader = XmlReader.Create("X:\vi.php.webintents")
Dim feedContent = SyndicationFeed.Load(feedReader)
If feedContent Is Nothing Then Return
For Each item As Object In feedContent.Items
messageList.Add(Convert.ToString(item.Title.Text))
Next
End Using
lbl_warnings.Text = String.Join(vbNewLine & vbNewLine, messageList)
End Sub
End Class
Replace "X:\vi.php.webintents" with your file location.
For System.ServiceModel.Syndication to be available, you need to add System.ServiceModel.dll to your references (.NET 4.0). For .NET 3.5 you would use System.ServiceModel.Web.dll
I used this answer as a base for SyndicationFeed usage in this example.
Related
I don't normally post on forums because I try to find information for myself, and ask as an absolute last resort. I've tried scouring the net for answers, but I'm only receiving about half of the answer I'm looking for.
I'm currently building an application that deals with state law. There's one combo box and one text box. One for the offense title, and one for the numerical code for that particular code section. So say if I select "Kidnapping", it prepopulates the text box below it with "11-5-77", for example.
The method I've been using for, oh, about the last hour now, is:
If AWOffenseTitle.Text = "Kidnapping" Then
AWCN.Text = "11-5-77"
ElseIf AWOffenseTitle.Text = "False Imprisonment" Then
AWCN.Text = "11-5-78"
With AWOffenseTitle being the combo box name, and AWCN being the text box name. While this has proved to work perfectly well so far, I'm sure you can imagine with hundreds of offense titles, this is going to take a ridiculously long time. Well, I finally found a spreadsheet with offense titles and their respective title codes. What I'm looking to do is create two text files within a folder in the local directory "Offenses". One with a vertical list of offenses, and one with a vertical list of offense code numbers that populate the same lines in each. What I'm looking to do is populate the combo box with the contents of text file one (which I can do already), but then selecting an offense title will read the second text file and display it's proper title code. That's what has me at a loss. I'm relatively well-versed with vb.NET, but I'm not an expert by any means.
I'm hoping someone here will be able to provide a code example and explain it to me line-by-line so I can gain a better understanding. I want to get more proficient with VB although it's not so popular anymore. I've been using VB since 6.0, but not on a regular basis. More on a sporadic project kind of basis.
I really appreciate any assistance anyone might be able to provide, and if you need more information, I'd be glad to answer any questions. I tried to be as thorough as I could.
Thank you in advance!
First, you need to retrieve your data. I demonstrated using an Sql Server database containing a table named Offenses with columns named OffenseTitle and OffenseCode. You will have to change this code to match your situation.
Private Function GetOffenseData() As DataTable
Dim dt As New DataTable
Using cn As New SqlConnection("Your connection string"),
cmd As New SqlCommand("Select OffenseTitle, OffenseCode From Offenses;")
cn.Open()
dt.Load(cmd.ExecuteReader)
End Using
Return dt
End Function
As the Form loads, set the properties of the ComboBox. DisplayMember matches the name of the title column and ValueMember is the name of the code column.
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Dim dt = GetOffenseData()
ComboBox1.DisplayMember = "OffenseTitle"
ComboBox1.ValueMember = "OffenseCode"
ComboBox1.DataSource = dt
End Sub
Then when the selected item in the combo changes, just set the .Text property of TextBox to the SelectedValue in the combo and your code appears.
Private Sub ComboBox1_SelectionChangeCommitted(sender As Object, e As EventArgs) Handles ComboBox1.SelectionChangeCommitted
TextBox1.Text = ComboBox1.SelectedValue.ToString
End Sub
There are other ways to do this if your data source is other than a database. Please advise if you need additional help.
In addition to HardCode's comment and Mary's detailed answer, I can only add an answer that's somewhere in between them.
It might be the case, that the information is not taken from a database, but from another source, like a text/data file or a web service. So it might be useful to create an abstraction for the data source you actually use.
First, I create a class or struct that will hold the data for each combo box item.
Class Offense
Public ReadOnly Property Title As String
Public ReadOnly Property Code As String
Public Sub New(title As String, code As String)
Me.Title = title
Me.Code = code
End Sub
End Class
Next, you need a method that retrieves a list of offenses that you can bind to your combo box. It's entirely up to you how you fill/fetch the offenses list. I have simply hard coded your two values here.
Private Function GetOffenseData() As List(Of Offense)
Dim offenses As New List(Of Offense)
offenses.Add(New Offense("Kidnapping", "11-5-77"))
offenses.Add(New Offense("False Imprisonment", "11-5-78"))
Return offenses
End Function
At a certain moment (probably in your form's Load event handler), you need to initialize your combo box. Just like Mary did, I use data binding.
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
AWOffenseTitle.DropDownStyle = ComboBoxStyle.DropDownList
AWCN.ReadOnly = True
AWOffenseTitle.DisplayMember = NameOf(Offense.Title)
AWOffenseTitle.ValueMember = NameOf(Offense.Code)
AWOffenseTitle.DataSource = GetOffenseData()
End Sub
Note that I use the NameOf operator to get the desired property names of the Offense class. If you ever decide to rename the properties of your Offense class, you will be able to easily detect where they are used, since the compiler will complain if your code still uses the wrong property names somewhere.
Finally, the app needs to react to combo box value changes, so that the text box will show the corresponding offense code. Mary used an event handler for the SelectionChangeCommitted event, but I use a handler for the SelectedIndexChanged event instead:
Private Sub AWOffenseTitle_SelectedIndexChanged(sender As Object, e As EventArgs) Handles AWOffenseTitle.SelectedIndexChanged
AWCN.Text = AWOffenseTitle.SelectedValue
End Sub
(Up to now, I was not aware of the SelectionChangeCommitted event of the ComboBox control. I will need to look into this event to see if it is actually a better choice for this scenario, but I found that the SelectedIndexChanged event does the job just fine, so for now I sticked with that event, since I am more familiar with it.)
So basically, I believe I am using the correct code yet the database will still not update. It will work for the current session, however, when I stop and restart the program, it appears that the data has not been updated in the database.
The really interesting part is that I am using the same method to update the database elsewhere, which when used and session restarted, the database has been updated.
p.s. I also have the same adapters and binding sources set up etc on both forms
I am so confused, help pls
Code that I believe is correct but is not working: (updating on another form so I have one place where all forms update hence FRMMain. etc)
Private Sub btnConfirm_Click(sender As Object, e As EventArgs) Handles btnConfirm.Click
Dim CurrentPoints As Integer
Dim UpdatedPoints As Integer
CurrentPoints = FRMMain.MyDBDataSet.Tables("TBLPupil").Rows(looopcount)(15)
UpdatedPoints = CurrentPoints + stfPoints
FRMMain.MyDBDataSet.Tables("TBLPupil").Rows(looopcount)(15) = UpdatedPoints
FRMMain.TBLPupilTableAdapter.Update(MyDBDataSet.TBLPupil)
FRMMain.TBLPupilTableAdapter.Fill(MyDBDataSet.TBLPupil)
End Sub
Code that I am using in another form that that DOES work:
Private Sub BtnYes_Click(sender As Object, e As EventArgs) Handles BtnYes.Click
Dim Points As Integer = FRMPupil.Pointss
Dim Cost As Integer = FRMPupil.RewardCost
Points = Points - Cost
FRMPupil.LePoints = Points
MyDBDataSet.Tables("TBLPupil").Rows(FRMLogin.DBLocation)(15) = Points
FRMMain.TBLPupilTableAdapter.Update(MyDBDataSet.TBLPupil)
FRMMain.TBLPupilTableAdapter.Fill(MyDBDataSet.TBLPupil)
Me.Hide()
End Sub
My code is correct but is not working.
No, if it is not working, then it is not correct!
There are different things you can do: DRY, Dont Repeat Yourself. You are repeating the code for updating points at several places in your code. This is error prone. Write it once and re-use it, e.g. by applying the the Repository Pattern. It makes it easier to detect errors and correct them. It allows you to re-use code that has already been tested in other scenarios (on another form).
Debug, debug, debug. Place breakpoints in the not working methods and see what happens. Do all the variables have the expected values? E.g., does looopcount have the same value as FRMLogin.DBLocation? There must be a difference somewhere. See: Navigating through Code with the Debugger or the more recent article Debug your Hello World application with Visual Studio 2017.
I'm trying to add a file unzipper to my application, so I googled a little and stumbled on the sevenzipsharp library that is able to extract the most common archive formats.
So I for testing I created a simple application with a windows form.
So the entered data is the file location C:\Users\jeee\Desktop\CriticalSubPrintout.rar and the extract location C:\Users\jeee\Desktop\Test Extract
I added some code, without any documentation.. not my strong side apparently..
Imports SevenZip
Public Class Archiver
Private Sub btnExtractArchive_Click(sender As Object, e As EventArgs) Handles btnExtractArchive.Click
Dim Extractor As New SevenZipExtractor(tbExtractFile.Text)
Extractor.ExtractArchive(tbExtractPath.Text)
End Sub
End Class
This causes an error when I try and run the code
Can anyone provide a sample code, or a link to a good example how-to-use SevenZipSharp? Because I searched and can't find any VB.NET samples.
Or maybe just help me figure out what I need to do.
Thanks.
You need to call SevenZipBase.SetLibraryPath with the path to 7z.dll, and make sure that you are using the correct version for your application (32- or 64-bit). e.g.
SevenZipBase.SetLibraryPath("C:\Dev\7z.dll")
Dim Extractor As New SevenZipExtractor(tbExtractFile.Text)
Extractor.ExtractArchive(tbExtractPath.Text)
In my program I have a preview, and edit side.
When you edit using the text boxes on the edit side(right side) and click "save", It should change the label on the right side (preview side). Although when you exit the program and re-open, all the data you entered has disappeared!,
I have tried the below code and had no luck as my result.
Public Class Form1
Private Shared NameBasic As Integer
Public Sub New()
InitializeComponent()
lblNameBasic.Text = Convert.ToString(NameBasic)
End Sub
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
NameBasic = txtFirstBasic.Text
lblNameBasic.Text = Convert.ToString(NameBasic)
End Sub
End Class
Also my goal is to have it be able to take it on a flashdrive onto any computer and have that data still saved within the exe. Is this even manageable? (I am more of a web based programmer so I am a bit new to this)
You need to write values to a text file at the same location of the exe. and read it. you will need both exe and the textfile.
OR
You will need to write a dll on run-time and write some values while closing the application. this will be more secure then the text file. here you will need both exe and dll to be copied into flash drive
OR
the application setting as spoken by others..
Most simply put, I want to connect to a built in web cam in my computer using visual basic, take a single picture, and save that in a file. I have spent about an hour or so looking for a reasonable way to do this, and have found a few suggestions. Unfortunately many the methods that I have tried seem unnecessarily complicated and I have yet to see one of them work on my computer. For example, I have tried using the icam class referenced in several places, where this code
Public Class Form1
Private Sub Snap()
Dim Webcam As iCam = New iCam
Webcam.initCam(PictureBox1.Handle.ToInt32)
Application.DoEvents()
If Webcam.iRunning Then
PictureBox2.Image = Webcam.copyFrame(PictureBox1, New RectangleF(0, 0, PictureBox1.Width, PictureBox1.Height))
End If
Webcam.closeCam()
Webcam = Nothing
End Sub
Private Sub PictureBox2_Click(sender As Object, e As EventArgs) Handles PictureBox2.Click
End Sub
End Class
Threw this error:
An unhandled exception of type 'System.InvalidOperationException' occurred in facerecognition.exe
Additional information: An error occurred creating the form. See Exception.InnerException for details. The error is: Failed to initialize because CategoryName is missing.
While with some work I could probably get the class functioning as it is meant to, the issue remains that there is really no simple and clean solution to this that I know of. Does anyone have a better idea of how to do this?