Читать книгу Excel 2019 Power Programming with VBA - Michael Alexander, Dick Kusleika - Страница 76

In the context of Excel macros, relative means relative to the currently active cell. Thus, you should use caution with your active cell choice—both when you record the relative reference macro and when you run it.

First, make sure that the Chapter 2 Sample.xlsm file is open. (This file is available on this book's companion website.) Then use the following steps to record a relative-reference macro:

1 Select the Use Relative References toggle button from the Developer tab, as shown in Figure 2.5.FIGURE 2.5 Recording a macro with relative references

2 Before recording, make sure that cell A1 is selected.

3 Select Record Macro from the Developer tab.

4 Name the macro AddTotalRelative.

5 Choose This Workbook in the Store Macro In drop-down.

6 Click OK to start recording.

7 Select cell A16 and type Total in the cell.

8 Select the first empty cell in Column D (D16), type = COUNTA(D2:D15), and then press Enter.

9 Click Stop Recording on the Developer tab to stop recording the macro.

At this point, you have recorded two macros. Take a moment to examine the code for your newly created macro.

Select Macros from the Developer tab to open the Macro dialog box. Here, choose the AddTotalRelative macro and click Edit.

Again, this opens the Visual Basic Editor to show you the code that was written when you recorded your macro. This time, your code looks something like the following:

Sub AddTotalRelative() ActiveCell.Offset(15, 0).Range("A1").Select ActiveCell.FormulaR1C1 = "Total" ActiveCell.Offset(0, 3).Range("A1").Select ActiveCell.FormulaR1C1 = "=COUNTA(R[-14]C:R[-1]C)" End Sub

Notice that there are no references to any specific cell ranges at all (other than the starting point "A1"). Let's take a moment to look at what the relevant parts of this VBA code really mean.

Notice that in line 2, Excel uses the Offset property of the active cell. This property tells the cursor to move a certain number of cells up or down and a certain number of cells left or right.

The Offset property code tells Excel to move 15 rows down and 0 columns across from the active cell (in this case, A1). There's no need for Excel to select a cell explicitly, as it did when recording an absolute reference macro.

To see this macro in action, delete the total row and do the following:

1 Select cell A1.

2 Select Macros from the Developer tab.

3 Find and select the AddTotalRelative macro.

4 Click the Run button.

5 Now select cell F1.

6 Select Macros from the Developer tab.

7 Find and select the AddTotalRelative macro.

8 Click the Run button.

Notice that this macro, unlike your previous macro, works on both sets of data. Because the macro applies the totals relative to the currently active cell, the totals are applied correctly.

For this macro to work, you simply need to ensure that

 You've selected the correct starting cell before running the macro.

 The block of data has the same number of rows and columns as the data on which you recorded the macro.

Ideally, this simple example has given you a firm grasp of macro recording of both absolute and relative references.