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Thread: Listbox: Delete empty lines...

  1. #1

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    Listbox: Delete empty lines...

    hey guys, ive been searching the whols google, and i couldnt find a ny solution.. i was wondering if someone here can help me out, i am loading a listbox items from a .txt files, and sometimes there are empty lines, there is a way i can delete them?

  2. #2
    VB Addict Pradeep1210's Avatar
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    Re: Listbox: Delete empty lines...

    Try something like this:
    vb.net Code:
    1. Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
    2.     Dim fileContents As String = File.ReadAllText("C:\temp\test.txt")
    3.     Dim splitter() As Char = {Chr(13)}
    4.     Dim listSource() As String = fileContents.Split(splitter, StringSplitOptions.RemoveEmptyEntries)
    5.     ListBox1.DataSource = listSource
    6. End Sub

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  3. #3
    PowerPoster isnoend07's Avatar
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    Re: Listbox: Delete empty lines...

    Why don't you just not add the line if blank:
    With List1
    If LineToAdd <> "" then
    .addItem LineToAdd
    end with
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  4. #4
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    Re: Listbox: Delete empty lines...

    After loading the listbox from the file:
    vb Code:
    1. Dim i As Integer = 0
    2. With Me.lstListBox.Items
    3. While i < .Count
    4.        If CStr(.Item(i)) = "" Then
    5.               .RemoveAt(i)
    6.        Else
    7.               i += 1
    8.        End If
    9. End While
    10. End With
    Last edited by minitech; May 13th, 2009 at 08:11 PM. Reason: Added "End With". Oops!

  5. #5
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    Re: Listbox: Delete empty lines...

    You might be able to use LINQ to do something like this:
    vb.net Code:
    1. ListBox1.Items = From o As Object In ListBox1.Items _
    2.                  Where o.ToString <> String.Empty _
    3.          Select o
    (Not tested, might not work the way I expect it to)

    However as mentioned, it is much better to not load the strings into your listbox in the first place.

  6. #6
    VB Addict Pradeep1210's Avatar
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    Re: Listbox: Delete empty lines...

    Quote Originally Posted by NickThissen View Post
    You might be able to use LINQ to do something like this:
    vb.net Code:
    1. ListBox1.Items = From o As Object In ListBox1.Items _
    2.                  Where o.ToString <> String.Empty _
    3.          Select o
    (Not tested, might not work the way I expect it to)

    However as mentioned, it is much better to not load the strings into your listbox in the first place.
    The Items collection of listbox can't be assigned that way because it is read only.

    Here is the correct way to do that, which is more or less equivalent of the non-LINQ version in my previous post:
    vb.net Code:
    1. ListBox1.DataSource = (From o As Object In ListBox1.Items _
    2.                       Where o.ToString <> String.Empty _
    3.                       Select o).ToList
    Pradeep, Microsoft MVP (Visual Basic)
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  7. #7
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    Re: Listbox: Delete empty lines...

    Quote Originally Posted by Pradeep1210 View Post
    The Items collection of listbox can't be assigned that way because it is read only.

    Here is the correct way to do that, which is more or less equivalent of the non-LINQ version in my previous post:
    vb.net Code:
    1. ListBox1.DataSource = (From o As Object In ListBox1.Items _
    2.                       Where o.ToString <> String.Empty _
    3.                       Select o).ToList
    I see. I suspected that but I wasn't in any position to test it. Thanks for clarifying.

  8. #8

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    Re: Listbox: Delete empty lines...

    its not working @_@"

  9. #9
    vb Coda .paul.'s Avatar
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    Re: Listbox: Delete empty lines...

    try this:

    vb Code:
    1. While ListBox1.FindStringExact("") <> -1
    2.     ListBox1.Items.Remove("")
    3. End While

  10. #10
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    Re: Listbox: Delete empty lines...

    Have you tried mine yet? It works with me.

  11. #11
    VB Addict Pradeep1210's Avatar
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    Re: Listbox: Delete empty lines...

    Quote Originally Posted by -Negative- View Post
    its not working @_@"
    Which one is not working??
    Pradeep, Microsoft MVP (Visual Basic)
    Please appreciate posts that have helped you by clicking icon on the left of the post.
    "A problem well stated is a problem half solved." Charles F. Kettering

    Read articles on My Blog 101 LINQ Samples JSON Validator XML Schema Validator "How Do I" videos on MSDN VB.NET and C# Comparison Good Coding Practices VBForums Reputation Saver String Enum Super Simple Tetris Game


    (2010-2013)
    NB: I do not answer coding questions via PM. If you want my help, then make a post and PM me it's link. If I can help, trust me I will...

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