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Access ListView SubItem Text by Column Header

Hi,

I have a ListView that I would like to access SubItem text from the selected row. The ListView is dynamically populated so I am not always sure what SubItem relates to the info I need. When populating the listview I included column headers but i am not sure how I can reference a selected listview item subItem by column header.

I can get the value with the following line, however i cant guarantee subitems(5) will be the data i need to get.

val = lvwData.Items(SelectedItemIndex).SubItems(5).Text

If I cant do this direct by column header name, is there some way i can determine the SubItems index by the known column name

Thank you for any advise

Howard Cantrell

Hi QuinnB74,

I do not know if this will help you ,but here is a sample that you might be able to modify...

'FORM 1

Public Class frmClickSubItem
Inherits System.Windows.Forms.Form

#Region " Windows Form Designer generated code "

Public Sub New()
MyBase.New()

'This call is required by the Windows Form Designer.
InitializeComponent()

'Add any initialization after the InitializeComponent() call

End Sub

'Form overrides dispose to clean up the component list.
Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
If disposing Then
If Not (components Is Nothing) Then
components.Dispose()
End If
End If
MyBase.Dispose(disposing)
End Sub

'Required by the Windows Form Designer
Private components As System.ComponentModel.IContainer

'NOTE: The following procedure is required by the Windows Form Designer
'It can be modified using the Windows Form Designer.
'Do not modify it using the code editor.
Friend WithEvents ListView1 As System.Windows.Forms.ListView
Friend WithEvents Label1 As System.Windows.Forms.Label
Friend WithEvents ColumnHeader1 As System.Windows.Forms.ColumnHeader
Friend WithEvents ColumnHeader2 As System.Windows.Forms.ColumnHeader
Friend WithEvents ColumnHeader3 As System.Windows.Forms.ColumnHeader
Friend WithEvents ColumnHeader4 As System.Windows.Forms.ColumnHeader
Friend WithEvents ColumnHeader5 As System.Windows.Forms.ColumnHeader
Friend WithEvents TextBox1 As System.Windows.Forms.TextBox
<System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
Me.ListView1 = New System.Windows.Forms.ListView
Me.ColumnHeader1 = New System.Windows.Forms.ColumnHeader
Me.ColumnHeader2 = New System.Windows.Forms.ColumnHeader
Me.ColumnHeader3 = New System.Windows.Forms.ColumnHeader
Me.ColumnHeader4 = New System.Windows.Forms.ColumnHeader
Me.ColumnHeader5 = New System.Windows.Forms.ColumnHeader
Me.Label1 = New System.Windows.Forms.Label
Me.TextBox1 = New System.Windows.Forms.TextBox
Me.SuspendLayout()
'
'ListView1
'
Me.ListView1.Anchor = CType((((System.Windows.Forms.AnchorStyles.Top Or System.Windows.Forms.AnchorStyles.Bottom) _
Or System.Windows.Forms.AnchorStyles.Left) _
Or System.Windows.Forms.AnchorStyles.Right), System.Windows.Forms.AnchorStyles)
Me.ListView1.Columns.AddRange(New System.Windows.Forms.ColumnHeader() {Me.ColumnHeader1, Me.ColumnHeader2, Me.ColumnHeader3, Me.ColumnHeader4, Me.ColumnHeader5})
Me.ListView1.FullRowSelect = True
Me.ListView1.GridLines = True
Me.ListView1.Location = New System.Drawing.Point(8, 8)
Me.ListView1.MultiSelect = False
Me.ListView1.Name = "ListView1"
Me.ListView1.Size = New System.Drawing.Size(458, 206)
Me.ListView1.TabIndex = 0
Me.ListView1.View = System.Windows.Forms.View.Details
'
'Label1
'
Me.Label1.Anchor = CType(((System.Windows.Forms.AnchorStyles.Bottom Or System.Windows.Forms.AnchorStyles.Left) _
Or System.Windows.Forms.AnchorStyles.Right), System.Windows.Forms.AnchorStyles)
Me.Label1.Location = New System.Drawing.Point(8, 222)
Me.Label1.Name = "Label1"
Me.Label1.Size = New System.Drawing.Size(190, 16)
Me.Label1.TabIndex = 1
Me.Label1.Text = "Label1"
'
'TextBox1
'
Me.TextBox1.Location = New System.Drawing.Point(212, 220)
Me.TextBox1.Name = "TextBox1"
Me.TextBox1.TabIndex = 2
Me.TextBox1.Text = "TextBox1"
'
'frmClickSubItem
'
Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
Me.ClientSize = New System.Drawing.Size(478, 244)
Me.Controls.Add(Me.TextBox1)
Me.Controls.Add(Me.Label1)
Me.Controls.Add(Me.ListView1)
Me.Name = "frmClickSubItem"
Me.Text = "Form1"
Me.ResumeLayout(False)

End Sub

#End Region

Private Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As IntPtr, ByVal lMsg As Integer, ByVal wParam As Integer, ByRef lParam As RECT) As Integer

Private Structure RECT
Public Left As Integer
Public Top As Integer
Public Right As Integer
Public Bottom As Integer
End Structure
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim i As Integer
Dim lvi As ListViewItem
Dim ch As ColumnHeader

For i = 0 To 10
lvi = New ListViewItem("Item" & i)
lvi.SubItems.Add("Subitems" & i * 1)
lvi.SubItems.Add("Subitems" & i * 2)
lvi.SubItems.Add("Subitems" & i * 3)
lvi.SubItems.Add("Subitems" & i * 4)
ListView1.Items.Add(lvi)
Next

For Each ch In ListView1.Columns
ch.Width = -2
Next
End Sub
Private Sub ListView1_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles ListView1.MouseDown
Label1.Text = "Column " & (GetListViewSubItem(Me.ListView1, New Point(e.X, e.Y)) + 1)
End Sub

Public Function GetListViewSubItem(ByVal listView1 As ListView, ByVal pt As Point) As Integer
Const LVM_FIRST As Integer = &H1000
Const LVM_GETSUBITEMRECT As Integer = LVM_FIRST + 56
Const LVIR_BOUNDS As Integer = 0

Dim myrect As RECT
Dim lvitem As ListViewItem = listView1.GetItemAt(pt.X, pt.Y)
If lvitem Is Nothing AndAlso listView1.SelectedItems.Count > 0 Then
lvitem = listView1.SelectedItems(0)
End If
Dim intLVSubItemIndex As Integer = -1
Dim LVSubItem As ListViewItem.ListViewSubItem = Nothing

If Not (lvitem Is Nothing) Then
Dim intSendMessage As Integer
Dim i As Integer
lvitem.UseItemStyleForSubItems = False
For i = 1 To lvitem.SubItems.Count - 1
LVSubItem = lvitem.SubItems(i)
myrect = New RECT
myrect.Top = i
myrect.Left = LVIR_BOUNDS
intSendMessage = SendMessage(listView1.Handle, LVM_GETSUBITEMRECT, lvitem.Index, myrect)
If pt.X < myrect.Left Then
LVSubItem = lvitem.SubItems(0)
LVSubItem.ForeColor = Color.Red
intLVSubItemIndex = 0
TextBox1.Text = LVSubItem.Text
Exit For
ElseIf pt.X >= myrect.Left And pt.X <= myrect.Right Then
intLVSubItemIndex = i
LVSubItem.ForeColor = Color.Orange
TextBox1.Text = LVSubItem.Text
Exit For
Else
LVSubItem = Nothing
End If
Next i
End If
If LVSubItem Is Nothing OrElse lvitem Is Nothing Then
intLVSubItemIndex = -1
End If
Return intLVSubItemIndex
End Function

End Class

QuinnB74

ASKER

Thanks for the suggestion however the SubItem I am looking for is actually hidden from view (colWidth = 0) so I dont think your solution will apply to my situation. Sorry, I should have been clearer earlier.

Without getting too into it, I have inherited some code whereby the previous developer had a listview to display a dataTable. This dev implemented column sorting on the listview, however any selection of the listview for action (ie delete) uses the listview selected index and passes that to the function which does the delete. the Delete function uses the listview index to lookup the record ID in the backend Datatable and then performs the action. Works great if the listview is unsorted as the indexes will line up, unfortunately ppl want the sort feature.

I thought the easiest fix was to query the listview for the ID (btw, this is not always limited to one ID, it references multiple foreign keys that i need to perform action on depending on user input) which is added during population with a column width of 0.

Thank you
Q

ASKER CERTIFIED SOLUTION

Bob Learned

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QuinnB74

ASKER

Thank You Kindly. It seems so logical now.