1. CS 106 Computing Fundamentals II Chapter 73 “Ranges”
Herbert G. Mayer, PSU CS
status 6/24/2013
Initial content copied verbatim from
CS 106 material developed by
CS professors: Cynthia Brown & Robert Martin

2. Syllabus Ranges Range is a Collection of Cells Use ForEach with Range
One-Dimensional Sample
Two-Dimensional Sample

3. Ranges
Unlike many of our programming concepts, Range is particular to Excel
Look for more detail in demo ForEachForNext
We show how to use a For Each loop with a Range, and contrast with a For variable nested loop that will help prepare us to deal with arrays

4. Range is a Collection of Cells
VBA in Excel has a data type Range
A Range can be a single cell, a block of cells, or a group of blocks of cells (we’ll stick with the first two possibilities)
You declare a Range variable in the usual way:
Dim workArea As Range
Dim aCell As Range

5. Use For Each with Range
For Each loop is used when you want to do the same thing to every item in a collection
A Range is a collection of cells
This loop clears all cells in global range workArea:
Sub ClearCells()
Dim aCell As Range
For Each aCell In workArea
aCell.Value = Empty
Next aCell
End Sub

6. Put a 1 in Each Cell in a Range
Sub ForEachDemo() Dim aCell As Range For Each aCell In workArea aCell.Value = 1 Next aCell End Sub

7. Treat Cells Differently
If you don’t want to do the same thing with each cell, then use a different kind of loop
For loops using variables work very well in this case
For a range that is just a single row or column, one loop is fine
For a two-dimensional range, you need nested loops

8. One-Dimensional Example (row)
To set elements 1 to size of the first row to two times their column index: For colNdx = 1 To size Cells(1, colNdx) = 2 * colNdx Next colNdx

9. Two-Dimensional Example
Sub ForVariableDemo() Dim rowNdx, colNdx As Long For rowNdx = 1 To size For colNdx = 1 To size Cells(rowNdx, colNdx).Value = rowNdx + colNdx Next colNdx Next rowNdx End Sub