Efficient way to delete entire row if cell doesn't contain '@' [duplicate]

Solution 1:

You don't need a loop to do this. An autofilter is much more efficient. (similar to cursor vs. where clause in SQL)

Autofilter all rows that don't contain "@" and then delete them like this:

Sub KeepOnlyAtSymbolRows()
    Dim ws As Worksheet
    Dim rng As Range
    Dim lastRow As Long

    Set ws = ActiveWorkbook.Sheets("Sheet1")

    lastRow = ws.Range("E" & ws.Rows.Count).End(xlUp).Row

    Set rng = ws.Range("E1:E" & lastRow)

    ' filter and delete all but header row
    With rng
        .AutoFilter Field:=1, Criteria1:="<>*@*"
        .Offset(1, 0).SpecialCells(xlCellTypeVisible).EntireRow.Delete
    End With

    ' turn off the filters
    ws.AutoFilterMode = False
End Sub

NOTES:

• .Offset(1,0) prevents us from deleting the title row
• .SpecialCells(xlCellTypeVisible) specifies the rows that remain after the autofilter has been applied
• .EntireRow.Delete deletes all visible rows except for the title row

Step through the code and you can see what each line does. Use F8 in the VBA Editor.

Solution 2:

Have you tried a simple auto filter using "@" as the criteria then use

specialcells(xlcelltypevisible).entirerow.delete

note: there are asterisks before and after the @ but I don't know how to stop them being parsed out!

Solution 3:

Using an example provided by user shahkalpesh, I created the following macro successfully. I'm still curious to learn other techniques (like the one referenced by Fnostro in which you clear content, sort, and then delete). I'm new to VBA so any examples would be very helpful.

   Sub Delete_It()
    Dim Firstrow As Long
    Dim Lastrow As Long
    Dim Lrow As Long
    Dim CalcMode As Long
    Dim ViewMode As Long

    With Application
        CalcMode = .Calculation
        .Calculation = xlCalculationManual
        .ScreenUpdating = False
    End With

    With ActiveSheet
        .Select
        ViewMode = ActiveWindow.View
        ActiveWindow.View = xlNormalView
        .DisplayPageBreaks = False

        'Firstrow = .UsedRange.Cells(1).Row
        Firstrow = 2
        Lastrow = .Cells(.Rows.Count, "E").End(xlUp).Row

        For Lrow = Lastrow To Firstrow Step -1
            With .Cells(Lrow, "E")
                If Not IsError(.Value) Then
                    If InStr(.Value, "@") = 0 Then .EntireRow.Delete
                End If
            End With
         Next Lrow
        End With

    ActiveWindow.View = ViewMode
    With Application
        .ScreenUpdating = True
        .Calculation = CalcMode
    End With

End Sub

Solution 4:

When you are working with many rows and many conditions, you better off using this method of row deletion

Option Explicit

Sub DeleteEmptyRows()
    Application.ScreenUpdating = False

    Dim ws As Worksheet
    Dim i&, lr&, rowsToDelete$, lookFor$

    '*!!!* set the condition for row deletion
    lookFor = "@"

    Set ws = ThisWorkbook.Sheets("Sheet1")
    lr = ws.Range("E" & Rows.Count).End(xlUp).Row

    ReDim arr(0)

    For i = 1 To lr
     If StrComp(CStr(ws.Range("E" & i).Text), lookFor, vbTextCompare) = 0 then
       ' nothing
     Else
        ReDim Preserve arr(UBound(arr) + 1)
        arr(UBound(arr) - 1) = i
     End If
    Next i

    If UBound(arr) > 0 Then
        ReDim Preserve arr(UBound(arr) - 1)
        For i = LBound(arr) To UBound(arr)
            rowsToDelete = rowsToDelete & arr(i) & ":" & arr(i) & ","
        Next i

        ws.Range(Left(rowsToDelete, Len(rowsToDelete) - 1)).Delete Shift:=xlUp
    Else
        Application.ScreenUpdating = True
        MsgBox "No more rows contain: " & lookFor & "or" & lookFor2 & ", therefore exiting"
        Exit Sub
    End If

    If Not Application.ScreenUpdating Then Application.ScreenUpdating = True
    Set ws = Nothing
End Sub