I have a VB project that is converted from VB6 to VB.NET.
In this, I have a MSFlexGrid that is used as an interop compatibiliy. That means it is somewhat converted to .NET, but internally, many of the mechanisms are still from VB6/COM.
I need to drag an image from a PictureBox (which is .NET) and drop it on the flexgrid.
This is what I do to initialize the drag:
Private Sub picStartSymbol_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles picStartSymbol.MouseDown
picStartSymbol.DoDragDrop(picStartSymbol.Image, DragDropEffects.Copy)
End Sub
And this is where I catch the drop in the FlexGrid:
Private Sub flxConstructionPoints_OLEDragDrop(ByVal sender As Object, ByVal e As AxMSFlexGridLib.DMSFlexGridEvents_OLEDragDropEvent) Handles flxConstructionPoints.OLEDragDrop
Dim image As Image
Dim oleImage As Object
oleImage = e.data.GetData(2) ''This gets an object of type 2 (bitmap)
''How to convert oleImage to a .NET Image?
End Sub
I don't have VB6 anymore so I can't test this but try adding a reference to Microsoft.VisualBasic.Compatibility and then call:
Dim image as Image = Microsoft.VisualBasic.Compatibility.VB6.IPictureToImage(oleImage)
or
Dim image as Image = Microsoft.VisualBasic.Compatibility.VB6.IPictureDispToImage(oleImage)
Related
I am attempting to get the filepath of an image that is dropped onto a button in VB. I have set the button to allow drop and I have set up this segment to hold the event code:
Private Sub btnDropZone_drop(sender As Object, e As EventArgs) Handles btnDropZone.DragDrop
End Sub
How would I go about getting the filepath from this event as a string? Thanks in advance!
A button is a pretty small drop target, but it would work the same as anything else: examine e As DragEventArgs:
Private Sub btnDropZone_drop(sender As Object,
e As EventArgs) Handles btnDropZone.DragDrop
'ToDo check the format to see what was dropped
Dim Files As String() = CType(e.Data.GetData(DataFormats.FileDrop), String())
For Each s As String In Files
ListBox1.Items.Add(Path.GetFileName(s))
Next
End Sub
When you are trying to figure out what to do in an event, always look up the meaning and contents of the eventargs
I am new to Visual Basic. I have installed Microsoft Visual Studio 2010. Created a new Windows Form Application. As an example, I made a simple program which will ask the end user to input 2 numbers and allow them to either add them or subtract the second number from the first one and display the output in a Textbox.
Now, I added another Subroutine which would be executed automatically when the Windows Form loads. This would calculate the width of the output Textbox and the Form Width and display at the bottom.
This is how the code looks like right now:
Public Class Form1
' Run this Subroutine initially to display the Form and Text box width
Private Sub Form_Load()
Label5.Text = TextBox3.Width
Label7.Text = Me.Width
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim a As Integer
Dim b As Integer
a = TextBox1.Text
b = TextBox2.Text
TextBox3.Text = a + b
End Sub
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
Dim a As Integer
Dim b As Integer
a = TextBox1.Text
b = TextBox2.Text
TextBox3.Text = a - b
End Sub
End Class
While everything works correctly for the addition and subtraction, it does not display the Form and output Textbox width in the Windows Form.
I think, Form_Load() is not executing properly.
I also tried, Form_Activate() but that did not work either.
Once I am able to do this, I would like to extend this concept to resize the output Textbox along with the Form resize. However, for the purpose of understanding I wanted to see if I can execute Form_Load() successfully.
Thanks.
Form_Load doesn’t execute. For now, it’s just any other method. In order to tell VB to make this method handle the Load event, you need to tell it so:
Private Sub Form_Load(sender As Object, e As EventArgs) Handles MyBase.Loasd
Label5.Text = TextBox3.Width
Label7.Text = Me.Width
End Sub
(And add the required parameters for the event.)
A few other remarks:
Ensure that Option Strict On is enabled in your project options at all times. This will make the compiler much stricter with your code and flag more errors. This is a good thing since these errors are potential bugs. In particular, your code is very lax with conversions between different data types, these should be made explicit.
Initialise variables when you declare them, don’t assign a value in a separate statement. That is, write this:
Dim a As Integer = Integer.Parse(TextBox1.Text)
(Explicit conversion added as well.)
If you want to make a control fill the form, you can just set its Dock property appropriately in the forms editor, instead of having to program this manually.
You need to add the Handle so the app executes it automatically:
Private Sub Form_Load(ByVal sender As Object, ByVal e As EventArgs) Handles MyBase.Load
'...
End Sub
I'm converting a VB6 application to VB.Net that draws on picture boxes. Naturally I read the fine manual and turn up this example here. I therefore produced a little project with a form containing only a picture box and tried the following:-
Private Sub Picture1_paint(ByVal sender As System.Object, _
ByVal e As System.EventArgs) _
Handles PictureBox1.Paint
Dim mygraphics As Graphics
mygraphics = PictureBox1.CreateGraphics
Dim pen As New Drawing.Pen(System.Drawing.Color.Red, 1)
mygraphics.DrawEllipse(pen, 0, 0, 100, 100)
pen.Dispose
End Sub
just like it says. But on running the application, the box turns up blank. Searching for help turned up a suggestion here that I should use a Frame instead, but the result was the same. I have checked that I'm not drawing in the background colour, and that the function is actually invoked.
What have I overlooked?
Paint handler has invalid type for EventArgs. It should be System.Windows.Forms.PaintEventArgs
Use e.Graphics property to obtain graphics instance.
mygraphics = e.Graphics
Reference Link MSDN - Control.Paint Event
I think e is of PainEventArgs type, with already contains a graphics object in e.Graphics. Use that instead.
Public Class Form1
Private Sub PictureBox1_Paint(ByVal sender As System.Object, _
ByVal e As System.Windows.Forms.PaintEventArgs) Handles PictureBox1.Paint
Dim pen As New Pen(Color.Red, 1)
e.Graphics.DrawEllipse(pen, 0, 0, 100, 100)
pen.Dispose()
End Sub
End Class
I'm really looking for a simple way to build VB.NET apps that use the GEplugin. So I have found this project that seems to do the dirty job I need: http://code.google.com/p/winforms-geplugin-control-library/
Well, all the code posted there around works on C#, but I need to have it on VB.NET. So I have tried this:
created a new 32-bit solution from VB.NET 2010 Express (I simply added
<PlatformTarget>x86</PlatformTarget >
inside the .vbproj file)
added a reference to FC.GEPluginCtrls.dll
inserted a GeWebBrowser control on the form
at the top of the code, added
Imports FC.GEPluginCtrls
then, in the form Load event, put this code:
InitializeComponent()
GeWebBrowser1.LoadEmbeddedPlugin()
Do
Loop Until GeWebBrowser1.PluginIsReady = False
GeWebBrowser1.CreateInstance(ImageryBase.Earth)
that, I think, would be equivalent to
http://code.google.com/p/winforms-geplugin-control-library/wiki/CreateInstance
So, the project compiles and doesn't get errors, but the GeWebBrowser control remains empty.
I actually wrote the library you are using. You are not listening for the PluginReady event. http://code.google.com/p/winforms-geplugin-control-library/wiki/PluginReady
To use it with VB simply convert the basic examples to VB -
http://code.google.com/p/winforms-geplugin-control-library/wiki/ExampleForm
Also, a loop polling PluginIsReady is totally unnecessary as the PluginReady event is asynchronous.
To show the earth all you would need is the following.
Private Sub Form1_Load( ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
GeWebBrowser1.LoadEmbeddedPlugin()
End Sub
To use the plugin when it has initialzesd use the PluginReady event. Something like.
Option Strict Off
Public Class Form1
Private Dim _ge as Object = Nothing
Private Sub GeWebBrowser1_PluginReady( ByVal sender As System.Object, ByVal e As FC.GEPluginCtrls.GEEventArgs) Handles GeWebBrowser1.PluginReady
_ge = e.ApiObject ' reference to the Google Earth Plugin object
MessageBox.Show(_ge.getApiVersion()) ' _ge is the plugin -use it just as in the javascript api...
End Sub
Private Sub Form1_Load( ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
GeWebBrowser1.LoadEmbeddedPlugin() ' load the plugin
End Sub
End Class
When I load the form where some text has been given to text box. All the text in that textbox is highlighted. I want vb not to load it this way.
How to fix it.
Thanks
Furqna
You could set the tab index on your textbox to something else so that it's not the lowest index.
You could set the TextBox1.SelectionLength = 0 in the form.activated event.
I don't like this as much because if the user had the text hilited and minized the application then they will lose the hilite, but is fairly easy to do. I guess you could use a flag to make sure it only did it on the first activate.
You could set a timer event in the load to clear it immediately after the load event, but that seems like overkill. I have worked at places where they had a standard function that happened on every form 100 ms after load because of problems such as this.
You could try this(it looks like a workaround):
Private Sub TextBox1_GotFocus(ByVal sender As Object, ByVal e As System.EventArgs) Handles TextBox1.GotFocus
TextBox1.SelectionStart = TextBox1.Text.Length
End Sub
It depends on the TabIndex of your TextBox, if it has the lowest TabIndex it gets focus and therefore it's Text is selected.
' VS.net 2013. Use the "Shown" event.
' GotFocus isn't soon enough.
Private Sub Form_Shown(sender As Object, e As EventArgs) Handles Me.Shown
TB.SelectionLength = 0
End Sub
Type 1 Method
Dim speech = CreateObject("sapi.spvoice")
speech.speak(TextBox1.Text)
Type 2 Method
Dim oVoice As New SpeechLib.SpVoice
Dim cpFileStream As New SpeechLib.SpFileStream
'Set the voice type male or female and etc
oVoice.Voice = oVoice.GetVoices.Item(0)
'Set the voice volume
oVoice.Volume = 100
'Set the text that will be read by computer
oVoice.Speak(TextBox1.Text, SpeechLib.SpeechVoiceSpeakFlags.SVSFDefault)
oVoice = Nothing
Type 3 Method
Imports System.Speech.Synthesis
Public Class Form1
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim spk As New SpeechSynthesizer
For Each voice As InstalledVoice In spk.GetInstalledVoices
ListBox1.Items.Add(voice.VoiceInfo.Name)
Next
ListBox1.SelectedIndex = 0
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim spk As New SpeechSynthesizer
spk.SelectVoice(ListBox1.SelectedItem.ToString)
spk.Speak(TextBox1.Text)
End Sub
End Class
This will also happen sometimes if The TextChanged or other similar Event is fired twice for the control.
When creating each form. Each object is indexed you can set the tab Index higher then the indexed object. Example: On the third form you put a text box in.
private void textBox1_TextChanged(object sender, EventArgs e)
This was the 12th object in the project, it would be indexed at 12. if you put the tab index higher then the indexed objects throughout the project. Tab index 1000 (problem solved.)
Have a great day.
Scooter