How to set Excel column widths to a certain number of pixels? - excel

Question

I have the following data set on a worksheet:
SheetName|ColumnIndex|Pixels
---------+-----------+------
abc |1 |50
abc |2 |150
def |1 |125
For each sheet, I'd like to set the column width to the appropriate number of pixels, using something like:
Sub setColumn (sheetName As string, columnIndex As long, pixels As long)
width=getWidthInCharacters(pixels)
ThisWorkbook.Sheets(sheetName).Cells(1, columnIndex).EntireColumn.ColumnWidth = width
End Sub
I haven't been able to figure out how to write the getWidthInCharacters() function. How do I convert pixels to characters, or possibly set .ColumnWidth to pixels directly?

Answer 1

I'm sorry to tell you, but in my experience, you can't. Column width is measured in points, and whilst you can - in theory - convert points to pixels, Excel won't listen very precisely when you assign them. They also seem to vary somewhat from monitor to monitor. Basically, points are fractions of inches, pixels are dots on the screen. Windows has a notion (right or wrong) of how many pixels there are to a point given a particular output device.
You can write a function that tweaks column width, but usually the approach has to be
Find the smallest contextual value that excel is willing to increment a column width by (say, store the original value, then assign .ColumnWidth = dblOriginal + 0.01. Check if columnwidth has changed - if it has, you just made a 1-pixel adjustment. If it hasn't, you need a bigger number than 0.01.
Find a final column width in pixels that you want, and repeat this first step until you've incremented the column width that many times.
Check the result, and see if it looks OK.
Word of warning: this is horrible, slow, and not good code, and if they've fixed column widths in versions of Excel after 2010, then you might be lucky and just be able to use a pixels-to-points function, convert and assign. There are some around, just in my experience they didn't give me consistent results on different screens on the same machine. Really weird that one.

Answer 2

.ColumnWidth does not depend on theme font selection, but pixel width does: https://support.microsoft.com/en-us/kb/214123
'pixel width of column A
Debug.Print (Columns("A").Width / 72) * ThisWorkbook.WebOptions.PixelsPerInch
After some reading and thinking, my solution:
Sub setColumnWidth(rColumnWidth As Range, iPixelWidth As Integer)
' set column width by pixels
' check status ScreenUpdating
Dim bScreenUpdatingState As Boolean
bScreenUpdatingState = Application.ScreenUpdating
' set status ScreenUpdating
If bScreenUpdatingState = True Then Application.ScreenUpdating = False
Dim iPointsPerInch As Byte
iPointsPerInch = 72
Dim iPixelsPerInch As Byte
iPixelsPerInch = ThisWorkbook.WebOptions.PixelsPerInch
' check 2 column widths: get iPointDelta
Dim rColumn As Range
Set rColumn = rColumnWidth.EntireColumn
rColumn.ColumnWidth = 1
Dim iPoint_1 As Single
iPoint_1 = rColumn.Width
rColumn.ColumnWidth = 2
Dim iPoint_2 As Single
iPoint_2 = rColumn.Width
Dim iPointDelta As Single
iPointDelta = iPoint_2 - iPoint_1
' set column width to iPixelWidth
Dim iPoint_New As Single
iPoint_New = iPixelWidth / iPixelsPerInch * iPointsPerInch
Dim iChar_New As Single
iChar_New = (iPoint_New - (iPointDelta - 1.5)) / iPointDelta
rColumn.ColumnWidth = iChar_New
' reset status ScreenUpdating
If bScreenUpdatingState = True Then Application.ScreenUpdating = True
End Sub
To run the sub setColumnWidth:
Sub call_setColumnWidth()
Dim r As Range
Set r = ActiveSheet.Range("C1")
setColumnWidth r, 70
End Sub