[RESOLVED][2008]Listview subitem search Q

[goldenix]

this is what I was able to find so far, but its still not working. im shure im on the right track tho. Im trying to search subitems for text & if found remove the whole row, exept the last bold one ->item2 item12

So I have 2 columns: the problem is that the code works after item 12, until item13 is reached, then i get error InvalidArgument=Value of '1' is not valid for 'index'. Parameter name: index

Column1     Column2
item1         item11
item2         item12
item3

thats my code.

        For Each ListViewItem In ListView1.Items
            If ListViewItem.SubItems(1) Is Nothing Then
                MessageBox.Show("nothing")
                exit for
            Else
                ListView1.Items.RemoveAt(0)
            End If

EDIT: see post 6 & 7 for solution

[jmcilhinney]

Don't use a For Each loop if you want to remove items from the collection. Use a For loop and count backwards. That way removing an item doesn't affect the positions of the items you're still yet to visit.

For index As Integer = myListView.Items.Count - 1 To 0 Step -1
    If myListView.Items(index).SubItems(1).Text = someText Then
        myListView.Items.RemoveAt(index)
    End If
Next index

Not to mention that you're not doing it right even if you were to use a For Each loop. You're removing the item at index zero every time, even if it's not the item at index zero that you matched. In that case you'd Remove(item), not RemoveAt(index). If you use a For Each loop then you have an item in the collection, not an index. In a For loop you have an index.

[goldenix]

..

Well I tried something similar before( waisted 6+ hours or so experimenting..But got same error as I mentioned before. Same error is also present if i use your code.

I mean i dont get it. if text is present it should remove the row, & if not do nothing, but instead it errors.. really weird.

[dynamic_sysop]

how about this ...

        Dim strItem As Integer = 12
        For x As Integer = ListView1.Items.Count - 1 To 0 Step -1
            '/// if there is no subitem listed, the Subitems count still shows as 1
            '/// if you have a Subitem, the Subitem count is 2 ( or more if you have several subitems in a row. )
            If ListView1.Items(x).SubItems.Count > 1 Then
                If ListView1.Items(x).SubItems(1).Text = "item" & strItem.ToString Then
                    ListView1.Items.Remove(ListView1.Items(x))
                    strItem -= 1
                End If
            End If
        Next

[goldenix]

how about this ...

aa i see ur tying to fool the program, but nothing will happen, because this value wont be found. VB. will t hink, its 1 value & will try to search for it. well i did experiment but it didnt work.

is there any other way to do this? I found some ppl mentioning FindItemWithText but i havent been able to find a working sample to understand how to use it.

[jmcilhinney]

I think I may have misunderstood. Are you saying that your items may have different numbers of subitems? If that's the case then you have to test the number of subitems first, then only compare the subitem text if the subitem exists. You can't get the subitem at index 1 if there is no subitem at index 1.

Dim items As ListView.ListViewItemCollection = Me.ListView1.Items
Dim item As ListViewItem
 
For index As Integer = items.Count - 1 To 0 Step -1
    item = items(index)
 
    If item.SubItems.Count > 1 AndAlso item.SubItems(1).Text = someText Then
        items.Remove(item)
    End If
Next index

That said, it would be far better practice to add the same number of subitems to each item. If there's no text to display in a particular column the create a subitem and set its Text to String.Empty. With this issue would never have occurred.

EDIT: Hmmm... I just realised that dynamic_sysop posted basically the same thing. What we've posted so far should certainly work, so I can only conclude that we have not understaood your issue properly. Please try to explain clearly and fully. Maybe you should start with exactly how you populated the ListView in the first place.

[dynamic_sysop]

i just had a look at FindItemWithText in a form & it's very self explanetory, you notice it says 2 overrides, well they are include subitems & start index
so i put this together as an example...

        '/// YOUR ITEMS TO SEARCH FOR WOULD GO HERE ...
        Dim strArray As String() = {"item11", "item12", "and so on..."}
        For Each s As String In strArray
            For x As Integer = ListView1.Items.Count - 1 To 0 Step -1
                '///SET THE 2ND PARAMETER TO TRUE TO INCLUDE SUBITEMS
                Dim l As ListViewItem = ListView1.FindItemWithText(s, True, x)
                If Not l Is Nothing Then
                    ListView1.Items.Remove(l)
                End If
            Next
        Next

hope it helps.

[goldenix]

..

..

@jmcilhinney
you understood me correctly the second column is only filled half way, after that there are no items. & your last example does work. I get it now. I didnt know you can count subitems & AndAlso was also new to me.

@dynamic_sysop
Your FindItemWithText sample does not error also.

Thank you both.