How to: Use a Formula to Determine which Cells to Format

• Sep 19, 2023
• 2 minutes to read

This example demonstrates how to create the rule that uses a formula as a criterion to apply a conditional format.

1. To create a new conditional formatting rule represented by the FormulaExpressionConditionalFormatting object, access the collection of conditional formats from the Worksheet.ConditionalFormattings property and call the ConditionalFormattingCollection.AddFormulaExpressionConditionalFormatting method. Pass the following parameters:

   • A CellRange object that defines a range of cells to which the rule is applied.
   • A string value that determines a formula to evaluate.
2. Specify formatting options to be applied to cells if the condition is true, using the ISupportsFormatting.Formatting property of the FormulaExpressionConditionalFormatting object.

Note

Transparency is not supported in conditional formatting.

To remove the FormulaExpressionConditionalFormatting object, use the ConditionalFormattingCollection.Remove, ConditionalFormattingCollection.RemoveAt or ConditionalFormattingCollection.Clear methods.

View Example

ConditionalFormatting.cs

// Create the rule to shade alternate rows without applying a new style.
FormulaExpressionConditionalFormatting cfRule = worksheet.ConditionalFormattings.AddFormulaExpressionConditionalFormatting(worksheet.Range["$A$2:$G$15"], "=MOD(ROW(),2)=1");
// Specify formatting options to be applied to cells if the condition is true.
// Set the background color to light blue.
cfRule.Formatting.Fill.BackgroundColor = Color.FromArgb(255, 0xBC, 0xDA, 0xF7);

ConditionalFormatting.vb

' Create the rule to shade alternate rows without applying a new style.
Dim cfRule As FormulaExpressionConditionalFormatting = worksheet.ConditionalFormattings.AddFormulaExpressionConditionalFormatting(worksheet.Range("$A$2:$G$15"), "=MOD(ROW(),2)=1")
' Specify formatting options to be applied to cells if the condition is true.
' Set the background color to light blue.
cfRule.Formatting.Fill.BackgroundColor = Color.FromArgb(255, &HBC, &HDA, &HF7)

The image below shows the result (the workbook is opened in Microsoft® Excel®). Alternate rows are shaded in light blue without applying a new style.