Listbox multi select

Question

User1542511682 posted

Hi there,

I have a listbox (20 Items) with multiselection and label that disply the selection and one button

So I wrote (it works fine)

Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim i As Integer
        Label1.Text = " "
        For i = 0 To ListBox1.Items.Count - 1
            If ListBox1.Items(i).Selected Then
                Label1.Text = Label1.Text & ListBox1.Items(i).Text & ", ")
 
            End If
        Next
    End Sub

Now when I click on button the label show lets say Item2,Item5,Item10,
How do I take off the last "," 
somthing like that  Item2,Item5,Item10

I used to do

Dim s As String = Trim(Label1.Text)
Label1.Text = s.Substring(0, s.Length - 1)
 
but it give me an error converting intiger to string
 
Thanks,
Oded Dror
 
 

Answer 1

User1992938117 posted

Use below code:

    Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim i As Integer
        Dim j As Integer
        Dim k As Integer
        Label1.Text = " "

        For i = 0 To ListBox1.Items.Count - 1
            If ListBox1.Items(i).Selected Then
                j = j + 1
            End If
        Next
        For i = 0 To ListBox1.Items.Count - 1
            If ListBox1.Items(i).Selected Then
                k = k + 1
                If (j = k) Then
                    Label1.Text = Label1.Text & ListBox1.Items(i).Text
                Else
                    Label1.Text = Label1.Text & ListBox1.Items(i).Text & ", "
                End If
            End If
        Next
    End Sub

Answer 2

User-1887867400 posted

Hi, you are appending ", " i.e a comma and a space. So, either you extract the substring upto (Length-2) or you use the following code:

Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
  Dim i As Integer
  Label1.Text = " "
  For i = 0 To ListBox1.Items.Count - 1
    If ListBox1.Items(i).Selected Then
      Label1.Text = Label1.Text & ListBox1.Items(i).Text & ", "
    End If
  Next

  'Obtain index of last comma (,)
  Dim lastCommIndex As Integer = Label1.Text.LastIndexOf(",")
  'Extract only required sub string.
  Label1.Text = Label1.Text.Substring(0, lastCommIndex)
End Sub

Answer 3

User-1887867400 posted

Hi Rajneesh your code may work but its using 2 loops and will increase the execution time of this code. So i think ur approach isn't more efficient.

Answer 4

User1992938117 posted

your code may work

It surely work. I have tested it..

its using 2 loops and will increase the execution time of this code

I am agree with you.

//Each developer has its own approach........

Answer 5

User1542511682 posted

Rajneesh,

Thank you for contacting me

I found another way

Left(Label1.Text, (Len(Label1.Text) - 1))

 

Thanks,

Oded Dror 

Answer 6

User1542511682 posted

vijaypant ,

Thank you for contacting me

I found another way

Left(Label1.Text, (Len(Label1.Text) - 1))

 

Thanks,

Oded Dror