Re: textbox keypress validation. - Visual Basic Discussion Boards

Re: How to save image/Picture in MsAccess Database using Vb.net

Dave Kreskowiak4-May-07 4:01

4-May-07 4:01

All you have to do is type "vb.net save image to access database[^]" into Google and you'll come up with dozens of examples.

But, since Access has a limited database file size, how you're doing it now would probably be the best way to do it. Of course, that's subject to your projects specifications and expected usage. For example, if you do a bunch of adding/deleting of the image records, it increases the need to compact and reapir the database on a regular schedule to keep the database file size down.

-- modified at 10:04 Friday 4th May, 2007

Dave Kreskowiak
Microsoft MVP
Visual Developer - Visual Basic
2006, 2007

Having Trouble using the Tab control in VB6

Vimalsoft(Pty) Ltd3-May-07 21:04

Vimalsoft(Pty) Ltd

3-May-07 21:04

I'm having trouble bringing the other tabs of my TabStrip Control to the
front so I can work on them. VB Help says to use ZOrder or Hide/Show
(depending on source), but the sample code doesn't fix the problem for the
design view.

I have 4 tabs in my control and can only get to the first one. None of my
other references cover this.

What am I missing?

Vuyiswa

Re: Having Trouble using the Tab control in VB6 [modified]

Dave Kreskowiak4-May-07 3:59

Dave Kreskowiak

4-May-07 3:59

It's been about 6 years since I've touched VB6, so I may get this wrong. But, IIRC, all you had to do was click on each tab to get it to show it's page, in design view.

Dave Kreskowiak
Microsoft MVP
Visual Developer - Visual Basic
2006, 2007

Re: Having Trouble using the Tab control in VB6

Vimalsoft(Pty) Ltd4-May-07 4:04

Vimalsoft(Pty) Ltd

4-May-07 4:04

Thats my problem,if you put a textbox, it will apear for all tabs. and when you draw a label, it wil not come on top of a Tab control

Vuyiswa

Re: Having Trouble using the Tab control in VB6

Dave Kreskowiak4-May-07 4:57

Dave Kreskowiak

4-May-07 4:57

Vuyiswamb wrote:
if you put a textbox, it will apear for all tabs.

Then the TextBox wasn't put on the page of the tab. It's actually sitting over the top of the entire TabControl.

This is usually caused by double-clicking the control in the ToolBox, then trying to move the control over the top of the TabControl. You MUST single-click the control in the ToolBox, then draw the control on the TabControl page. Click and hold the mouse button down on the TabControl and drag to draw the new control to size.

Dave Kreskowiak
Microsoft MVP
Visual Developer - Visual Basic
2006, 2007

textbox keypress validation.

Sonia Gupta3-May-07 19:08

Sonia Gupta

3-May-07 19:08

i was doing some validations on textbox keypress function.The characters , i wanted to get typed is from 0 to 9.This got implemented by the code
if(e.keychar="0" or e.keychar="1".......... till 9)
e.handled =false

In addition to these , i wanted to remove the character , it it get wrongly typed .... and for that i am using the back space key.
Now my question is what should i assign to e.keychar= ???
so as to validate the back space key for keypress function of textbox.

Re: textbox keypress validation.

Rupesh Kumar Swami3-May-07 19:52

Rupesh Kumar Swami

3-May-07 19:52

hi Nilish , use followin code on keypress event of text box

If( (Not System.Char.IsControl(e.KeyChar)) And (Not System.Char.IsDigit ( e.KeyChar ) ) ) Then
e.Handled = True
End If

Hope this help

Rupesh Kumar Swami
Software Engineer,
Integrated Solution,
Bikaner (India)

Re: textbox keypress validation.

Sonia Gupta3-May-07 22:06

Sonia Gupta

3-May-07 22:06

but where it is saying that on backspace key press i am making the e.handled=false.

Re: textbox keypress validation.

Rupesh Kumar Swami3-May-07 22:41

Rupesh Kumar Swami

3-May-07 22:41

hi Nilish,
note following line

not System.Char.IsControl(e.KeyChar))

Here IsControl include checks for all control key like Del,backspace etc.

Rupesh Kumar Swami
Software Engineer,
Integrated Solution,
Bikaner (India)

Re: textbox keypress validation.

BINOVAR3-May-07 22:48

BINOVAR

3-May-07 22:48

Put this code in key press event of the textbox which has to control the input....

If Char.IsLetter(e.KeyChar) Then
e.Handled =

True

MessageBox.Show("blocking alphabets,plz enter only Numerics")
End If

If Char.IsNumber(e.KeyChar) Then
e.Handled =

True

'MessageBox.Show("blocking numbers,plz enter only Alphabets")

End If

hope this vl be helpfull to u

Regards
Bino Varghese.

Re: textbox keypress validation. [modified]

Sonia Gupta4-May-07 0:06

Sonia Gupta

4-May-07 0:06

actually i wanted to allow typing for 0-9 and for backspace key
for 0-9 have been implemented
but for back space to happen , still there exist a problem.
i don't know the code.

-- modified at 6:22 Friday 4th May, 2007

Re: textbox keypress validation.

Rupesh Kumar Swami4-May-07 0:41

Rupesh Kumar Swami

4-May-07 0:41

hi NIlish ,

i m not 100% sure .but try these values

BackSpace Key Value -8
Delete Key Value-46

hope this helps

Rupesh Kumar Swami
Software Engineer,
Integrated Solution,
Bikaner (India)

Trig in vb [modified]

ummoops3-May-07 14:42

ummoops

3-May-07 14:42

Hi all,

Does anyone know if the trigonometry math functions return in degrees or radians and if it does the math in radians how do you convert from radians to degrees? (using VB.net 2005)

Thanks

-- modified at 21:00 Thursday 3rd May, 2007

There are 10 types of people in the world: those who understand binary and those who don't

Re: Trig in vb

Arun.Immanuel3-May-07 15:58

Arun.Immanuel

3-May-07 15:58

ummoops wrote:
Does anyone know if the trigonometry math functions return in degrees or radians

It will return in Radians.

ummoops wrote:
how do you convert from radians to degrees?

Use:rad*180/3.14

Regards,
Arun Kumar.A

Re: Trig in vb

ummoops3-May-07 16:27

ummoops

3-May-07 16:27

Thanks

There are 10 types of people in the world: those who understand binary and those who don't

execute in context of different user

TeachesOfPeaches3-May-07 11:35

TeachesOfPeaches

3-May-07 11:35

hi,

i would like to read the user name and the password from an ini file in vb6 and run the application in the context of this account (the platform is W2K or WXP). Can any one give me a clue how to accomplish that or what api do i need?
Many thanks for suggestions,

andreas

Re: execute in context of different user

Dave Kreskowiak4-May-07 3:45

Dave Kreskowiak

4-May-07 3:45

I think you're looking for the Win32 API function CreateProcessWithLogonW[^].

Dave Kreskowiak
Microsoft MVP
Visual Developer - Visual Basic
2006, 2007

Re: execute in context of different user

TeachesOfPeaches4-May-07 4:45

TeachesOfPeaches

4-May-07 4:45

yes,this is the one, thanks

Bubble sort an array of Structure

amatbrewer3-May-07 11:35

amatbrewer

3-May-07 11:35

I have an array of a structure similar to below:
Public Structure MyStructure
Public MyString as string
Public MyInt1 as Int
Public MyInt2 as int
end structure

Dim StructArray ()

I want a function that will sort the data by the MyString field.
Any suggestions?

Thanks in advance!

David Wilkes

Re: Bubble sort an array of Structure

TwoFaced3-May-07 13:35

TwoFaced

3-May-07 13:35

You can use the sort method found in the Array class. You can implement IComparable in your structure. Basically this allows objects of type MyStructure to be compared. Here is a simple example.

Public Class Form1
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim people As Person() = {New Person("Bob", "Smith"), New Person("Chris", "Adams")}
        Array.Sort(people)
        For Each p As Person In people
            Console.WriteLine(p.FirstName & ":" & p.LastName)
        Next
    End Sub
End Class

Public Structure Person
    Implements IComparable(Of Person)

    Public FirstName As String
    Public LastName As String

    Public Sub New(ByVal first As String, ByVal last As String)
        FirstName = first
        LastName = last
    End Sub

    Public Function CompareTo(ByVal other As Person) As Integer Implements System.IComparable(Of Person).CompareTo
        Return String.Compare(Me.LastName, other.LastName)
    End Function
End Structure

This will sort alphabetically by the LastName field. If you want to sort in descending order you could first call sort to put them in ascending order and then call array.reverse(YourArray) to put them in descedning order. There are other ways to allow for multiple different sorts. If you want to learn more about it try looking up the interfaces Icomparer, and Icomparable.

Checking for overlapping timespans

fp2billiards3-May-07 11:05

fp2billiards

3-May-07 11:05

I am trying to see if there is way to use the TimeSpan class to see if one timespan overlaps another. Maybe I am using the wrong class. For example, if I have a start date of 1/1/2007 and an End date of 4/1/2007 I want to know if that range overlaps another (example: 11/1/2006 to 3/1/2007) And if it does, by how many, minutes, days... etc...

Does any one have any ideas?

Thanks!

Re: Checking for overlapping timespans

Arun.Immanuel3-May-07 15:53

Arun.Immanuel

3-May-07 15:53

Do like this:

if s1>s2 and e1<e2 Then
  s1-e1 occurs inbetween s2-e2(So, Overlapping=e1-s1+1)
elseif s1<s2 and e1>e2 Then
  s2-e2 occurs inbetween s1-e1(So, Overlapping=e2-s2+1)
elseif s1 > s2 and s1 < e2 then
  Overlapping=e2-s1+1
elseif e1>s2 and e1<e2
  Overlapping=e1-s2+1
else
  Overlapping=0

Use appropriate classes to compare 2 dates.

Regards,
Arun Kumar.A

Using a filter on BindingSource with BindingList

Mightor3-May-07 9:44

Mightor

3-May-07 9:44

Hi there,

I've been messing with the DataGridView component and it's really quite cool what you can do with it. I have it working for the most part, apart from one thing. I can't seem to get filtering working. The code I have is fort testing purposes only, basically just to get to know how to work with the DGV. I did notice that bSource.SupportsFiltering was set to False and I have no idea how to change that.

Private Sub Dialog1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
    Dim bList As New System.ComponentModel.BindingList(Of ListItem)
    Dim bSource As New BindingSource()

    bSource.DataSource = bList

    ' ListItem has Name, ID and Important properties, which are String, Integer and Boolean
    ' respectively.

    bList.Add(New ListItem("Item 1", 1, True))
    bList.Add(New ListItem("Item 2", 2, False))
    bList.Add(New ListItem("Item 3", 3, True))
    bList.Add(New ListItem("Item 4", 4, False))

    DataGridView1.DataSource = bSource

    DataGridView1.ColumnHeadersVisible = False

    ' This makes sure that only 'Important' and 'Name' are shown and displayed
    ' in the correct order
    DataGridView1.Columns(2).DisplayIndex = 0
    DataGridView1.Columns(1).DisplayIndex = 1
    DataGridView1.Columns(0).DisplayIndex = 2
    DataGridView1.Columns(0).Visible = False

    DataGridView1.Columns(2).Width = 20
    DataGridView1.Columns(1).AutoSizeMode = DataGridViewAutoSizeColumnMode.Fill
    DataGridView1.GridColor = Color.White
    DataGridView1.RowHeadersVisible = False
    DataGridView1.SelectionMode = DataGridViewSelectionMode.FullRowSelect
End Sub

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
    Dim bSource As BindingSource = DataGridView1.DataSource
    bSource.Filter = "ID == 2"
    DataGridView1.Refresh()
End Sub

Basically, to test the filter, I wanted to press a button and then apply the filter and have the DGV display only the results of my filter action. I am sure that once I get the hang of the filtering, I can implement it fully in my main app. Does filtering just not work when using a BindingList as your data backend?

Gr,
Mightor

My sig was stolen by a blind monkey.

Re: Using a filter on BindingSource with BindingList

Dave Kreskowiak4-May-07 3:50

Dave Kreskowiak

4-May-07 3:50

You can't change the SupportsFiltering property. It's a readonly flag that tells you if the datasource the BS is bound to supports filtering. Since you're using a List, no, you can't do filtering. You have to use a data source that DOES support filtering, like a DataSet or DataTable, most likely fed data by an Access or SQL Server database.

Dave Kreskowiak
Microsoft MVP
Visual Developer - Visual Basic
2006, 2007

Re: Using a filter on BindingSource with BindingList

Mightor4-May-07 9:17

Mightor

4-May-07 9:17

Thanks. I've now implemented it with a DataTable which is fed by an XML file downloaded from the Web. It works a treat.

Gr,
Mightor

A diseased chipmunk hid my sig.

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