Custom rules
Custom Conditional Formatting rules give you the ability to test for any condition that can be expressed as a logical test. Excel offers an array of IS functions that test for various conditions and return TRUE or FALSE. The CELL function also returns the equivalent of TRUE or FALSE. You also use the logical_test portion of what you would enter in an IF formula to create a TRUE or FALSE calculation as well. Let’s see create a rule that will mark a cell in red if a user overwrites a formula with a static value, also known as a constant in Excel.
IS functions
Examples of IS functions include ISBLANK, ISNUMBER, and ISTEXT. Each IS function has a single reference argument where you reference a cell that you wish to test, and the function returns TRUE or FALSE. Let’s create a custom Conditional Formatting rule that will make a cell turn red if the user types over a formula:
- Select a range of cells, such as J10:L57, on the Custom Rules – Formulas...
