Autor
).Tengo un ListView con X items, cada item contiene X información, el ListView tiene 4 columnas y estas son:
Nombre | Tamaño | Estado | Atributos
En el cual cada columna guarda la información referente a un archivo de texto o .ini seleccionado.
El problema reside al momento de querer ordenar los items de cada columna al hacer click en ellos, y pasa lo siguiente:
Al momento de hacer click en cualquier columna excepto en la de "Tamaño", los items cogen su orden alfabético de manera correcta, pero... si lo hago con la columna "Tamaño" tan sólo se invierte su orden, entonces lo que quisiera es que, al momento de darle click, se ordenara según su peso.
El subitem en esa columna contendrá información en este formato: ##.## Bytes, ##.## KB, ##.## MB y ##.## GB. Donde # equivale al tamaño del item.
La manera para obtener el tamaño de cada item, se hace con esta función:
Código
internal static string GetDllSize(long Bytes)
{
const int Scale = 1024;
string[] Sizes = new string[] { "GB", "MB", "KB", "Bytes" };
long Max = (long)Math.Pow(Scale, Sizes.Length - 1);
foreach (string Order in Sizes)
{
if (Bytes > Max)
return string.Format("{0:##.##} {1}", decimal.Divide(Bytes, Max), Order);
Max /= Scale;
}
return "0 Bytes";
}
Entonces, como decía arriba, quisiera saber cómo ordenar estos items al hacer click en la columna, (eh si... ya sé que con el evento column_click), pues... como dije anteriormente ya lo he realizado sin problemas con los demás datos, que tan sólo son strings.
Por si sirve de algo, encontré un código en Visual Basic 6 (El cuál aún no me he dispuesto a convertir a C# por temor a perder tiempo fracasando en su conversión), que ordena sin problemas números, fechas y cadenas de texto, de éste me quiero guiar, pero no sé si haya una manera más eficiente en C#.
El código es el siguiente:
Código
Private Declare Function LockWindowUpdate Lib "user32" _
(ByVal hWndLock As Long) As Long
Private Declare Function GetTickCount Lib "kernel32" () As Long
Private Sub Form_Load()
With ListView1
' Add three columns to the list - one for each data type.
' Note that the data type is set in the column header's
' tag in each case
.ColumnHeaders.Add(, , "String").Tag = "STRING"
.ColumnHeaders.Add(, , "Number").Tag = "NUMBER"
.ColumnHeaders.Add(, , "Date").Tag = "DATE"
' Set the column alignment - has no bearing on the sorts.
.ColumnHeaders(1).Alignment = lvwColumnLeft
.ColumnHeaders(2).Alignment = lvwColumnRight
.ColumnHeaders(3).Alignment = lvwColumnCenter
' Populate the list with data
Dim l As Long
Dim dblRnd As Double
Dim dteRnd As Date
With .ListItems
For l = 1 To 1000
With .Add(, , "ListItem " & Format(l, "0000"))
dblRnd = (Rnd() * 10000) - 5000
dteRnd = (Rnd() * 1000) + Date
.ListSubItems.Add , , Format(dblRnd, "0.00")
.ListSubItems.Add , , Format(dteRnd, _
"dd/mm/yyyy")
End With
Next l
End With
End With
End Sub
Private Sub ListView1_ColumnClick(ByVal ColumnHeader As _
MSComctlLib.ColumnHeader)
On Error Resume Next
' Record the starting CPU time (milliseconds since boot-up)
Dim lngStart As Long
lngStart = GetTickCount
' Commence sorting
With ListView1
' Display the hourglass cursor whilst sorting
Dim lngCursor As Long
lngCursor = .MousePointer
.MousePointer = vbHourglass
' Prevent the ListView control from updating on screen -
' this is to hide the changes being made to the listitems
' and also to speed up the sort
LockWindowUpdate .hWnd
' Check the data type of the column being sorted,
' and act accordingly
Dim l As Long
Dim strFormat As String
Dim strData() As String
Dim lngIndex As Long
lngIndex = ColumnHeader.Index - 1
Select Case UCase$(ColumnHeader.Tag)
Case "DATE"
' Sort by date.
strFormat = "YYYYMMDDHhNnSs"
' Loop through the values in this column. Re-format
' the dates so as they can be sorted alphabetically,
' having already stored their visible values in the
' tag, along with the tag's original value
With .ListItems
If (lngIndex > 0) Then
For l = 1 To .Count
With .Item(l).ListSubItems(lngIndex)
.Tag = .Text & Chr$(0) & .Tag
If IsDate(.Text) Then
.Text = Format(CDate(.Text), _
strFormat)
Else
.Text = ""
End If
End With
Next l
Else
For l = 1 To .Count
With .Item(l)
.Tag = .Text & Chr$(0) & .Tag
If IsDate(.Text) Then
.Text = Format(CDate(.Text), _
strFormat)
Else
.Text = ""
End If
End With
Next l
End If
End With
' Sort the list alphabetically by this column
.SortOrder = (.SortOrder + 1) Mod 2
.SortKey = ColumnHeader.Index - 1
.Sorted = True
' Restore the previous values to the 'cells' in this
' column of the list from the tags, and also restore
' the tags to their original values
With .ListItems
If (lngIndex > 0) Then
For l = 1 To .Count
With .Item(l).ListSubItems(lngIndex)
strData = Split(.Tag, Chr$(0))
.Text = strData(0)
.Tag = strData(1)
End With
Next l
Else
For l = 1 To .Count
With .Item(l)
strData = Split(.Tag, Chr$(0))
.Text = strData(0)
.Tag = strData(1)
End With
Next l
End If
End With
Case "NUMBER"
' Sort Numerically
strFormat = String(30, "0") & "." & String(30, "0")
' Loop through the values in this column. Re-format the values so as they
' can be sorted alphabetically, having already stored their visible
' values in the tag, along with the tag's original value
With .ListItems
If (lngIndex > 0) Then
For l = 1 To .Count
With .Item(l).ListSubItems(lngIndex)
.Tag = .Text & Chr$(0) & .Tag
If IsNumeric(.Text) Then
If CDbl(.Text) >= 0 Then
.Text = Format(CDbl(.Text), _
strFormat)
Else
.Text = "&" & InvNumber( _
Format(0 - CDbl(.Text), _
strFormat))
End If
Else
.Text = ""
End If
End With
Next l
Else
For l = 1 To .Count
With .Item(l)
.Tag = .Text & Chr$(0) & .Tag
If IsNumeric(.Text) Then
If CDbl(.Text) >= 0 Then
.Text = Format(CDbl(.Text), _
strFormat)
Else
.Text = "&" & InvNumber( _
Format(0 - CDbl(.Text), _
strFormat))
End If
Else
.Text = ""
End If
End With
Next l
End If
End With
' Sort the list alphabetically by this column
.SortOrder = (.SortOrder + 1) Mod 2
.SortKey = ColumnHeader.Index - 1
.Sorted = True
' Restore the previous values to the 'cells' in this
' column of the list from the tags, and also restore
' the tags to their original values
With .ListItems
If (lngIndex > 0) Then
For l = 1 To .Count
With .Item(l).ListSubItems(lngIndex)
strData = Split(.Tag, Chr$(0))
.Text = strData(0)
.Tag = strData(1)
End With
Next l
Else
For l = 1 To .Count
With .Item(l)
strData = Split(.Tag, Chr$(0))
.Text = strData(0)
.Tag = strData(1)
End With
Next l
End If
End With
Case Else ' Assume sort by string
' Sort alphabetically. This is the only sort provided
' by the MS ListView control (at this time), and as
' such we don't really need to do much here
.SortOrder = (.SortOrder + 1) Mod 2
.SortKey = ColumnHeader.Index - 1
.Sorted = True
End Select
' Unlock the list window so that the OCX can update it
LockWindowUpdate 0&
' Restore the previous cursor
.MousePointer = lngCursor
End With
' Report time elapsed, in milliseconds
MsgBox "Time Elapsed = " & GetTickCount - lngStart & "ms"
End Sub
'****************************************************************
' InvNumber
' Function used to enable negative numbers to be sorted
' alphabetically by switching the characters
'----------------------------------------------------------------
Private Function InvNumber(ByVal Number As String) As String
Static i As Integer
For i = 1 To Len(Number)
Select Case Mid$(Number, i, 1)
Case "-": Mid$(Number, i, 1) = " "
Case "0": Mid$(Number, i, 1) = "9"
Case "1": Mid$(Number, i, 1) = "8"
Case "2": Mid$(Number, i, 1) = "7"
Case "3": Mid$(Number, i, 1) = "6"
Case "4": Mid$(Number, i, 1) = "5"
Case "5": Mid$(Number, i, 1) = "4"
Case "6": Mid$(Number, i, 1) = "3"
Case "7": Mid$(Number, i, 1) = "2"
Case "8": Mid$(Number, i, 1) = "1"
Case "9": Mid$(Number, i, 1) = "0"
End Select
Next
InvNumber = Number
End Function
Pues bien, también he leído éste artículo de la msdn, pero... nunca había manejado el tema de iComparer, por tal ando un poco perdido en él.
Si alguien pudiera echarme una mano, o al menos darme información sobre iComparer (un pequeño manual, o algo que me pueda servir para guiarme) se lo agradecería.
Gruß.
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