textbox length

[yewmeng]

hi all

my problem is how to insert a value to a textbox length

for example

 

i want to insert string "a" when the len(textbox1.text) = 3

 

please help me thx in advance

[techmanbd]

not sure exactly what you are saying but hopefully this is what you are looking for

 

if textbox1.text.length = 3 then

whereveryouwant.text = a

end if

[kas]

Not sure I fully understand where your string goes, but here's code to test the length of the text box's text

 

Private Sub TextBox1_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TextBox1.TextChanged
       If TextBox1.Text.Length = 3 Then
           TextBox1.Text &= "a"
       End If
   End Sub

 

Let me know if I've not understood your queestion.

 

kas

[yewmeng]

yeah is working

but still have some problem

coz the .net version i have is recognise , as decimal point instead of . so i want to clear the . and replace , when user key in .

i have try the code u posted at here but how to clear the .

[kas]

Try This:

Private Sub TextBox1_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox1.KeyPress
       e.Handled = True 'This effectively Cancels the Keypress
       If e.KeyChar <> "." Then
           e.Handled = False '
       Else
           TextBox1.Text &= ","
           TextBox1.SelectionStart = TextBox1.Text.Length
       End If
   End Sub

 

kas

[yewmeng]

yeah

is working good

 

how about this

Private Sub txtQuantityIn_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles txtQuantityIn.KeyPress

Dim keyAscii As Int16

keyAscii = Asc(e.KeyChar)

If keyAscii = 46 Then

MessageBox.Show("ajsdjha")

txtQuantityIn.Text = ""

End If

End Sub

 

i want to clear the textbox but cant. so how to clear it

[kas]

The solution to all these kinds of problems is the e.Handled statement. This controls whether the key press is allowed to be displayed or not.

 

Private Sub txtQuantityIn_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles txtQuantityIn.KeyPress
       e.Handled = True  ' Suppress the key press for now
       Dim keyAscii As Int16
       keyAscii = Asc(e.KeyChar)
       If keyAscii = 46 Then
           MessageBox.Show("ajsdjha")
           txtQuantityIn.Text = ""
       Else
           e.Handled = False  ' Allow the key press if not ASC(46)
       End If
   End Sub

 

kas

[kas]

In fact, slightly better code would be:

Private Sub txtQuantityIn_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles txtQuantityIn.KeyPress
       e.Handled = True  ' Suppress the key press for now
       If Asc(e.KeyChar) = 46 Then
           MessageBox.Show("ajsdjha")
           txtQuantityIn.Clear()
       Else
           e.Handled = False  ' Allow the key press if not ASC(46)
       End If
   End Sub

 

There is no benefit in declaring your Int16 variable.

 

kas

[yewmeng]

it working good thx so much

 

1 more question

how to check the value in listbox exist or not

i have try this code in a button

 

dim i as integer

for i = 0 to listbox1.lenght - 1

if listbox1.text = "abc" then

messagebox.show("aaaa")

end if

next

 

but no messagebox pop up but in my listbox has the value abc

[kas]

You were close. It should be:

 

If ListBox1.SelectedItem = "abc" Then MessageBox.Show("Hooray")

 

 

kas

[Heiko]

How about

 

      if myListBox.FindStringExact("abc") = Listbox.NoMatches then
       'nothing found
      else
       myListBox.SelectedIndex = myListBox.FindStringExact("abc")
      end if

[yewmeng]

yeah both of the code also working good....

thx kas and heiko

may god bless both of u ....

[yewmeng]

hi again

how about to obtain part of the string in the textbox when the textbox lenght = 3

 

lets say,input 123 to textbox1.text then how to obtain the value 3.

 

pls help me, thx in advance!

[kas]

Label1.Text = txtQuantityIn.Text.Chars(2)

 

(The length count of a string starts with zero, so you pick out element #2)

 

kas