بسم الله الرحمن الرحيم
السلام عليكم ورحمة الله وبركاته
Click Editor on the Editor toolbar and click Start Editing.

You can make calculations without being in an editing session; however, in that case, there is no way to undo the results.

Right-click the shapefile layer you want to edit and click Open Attribute Table.

Right-click the field heading for area and click Calculate Values.

If there is no field for area values, you can add a new field for area by clicking the Options button and selecting Add Field. However, to add a new field, you need to exit the editing session.

Check Advanced.

Type the following VBA statement in the first text box:


Dim dblArea as double
Dim pArea as IArea
Set pArea = [shape]
dblArea = pArea.area




Type the variable dblArea in the text box directly under the area field name.

Click OK.