public class XlCondFmtRuleColorScale :
    XlCondFmtRule

Public Class XlCondFmtRuleColorScale
    Inherits XlCondFmtRule

// Create an instance of the XlConditionalFormatting class. 
XlConditionalFormatting formatting = new XlConditionalFormatting();
// Specify cell ranges to which the conditional formatting rule should be applied (A1:A11 and C1:C11).
formatting.Ranges.Add(XlCellRange.FromLTRB(0, 0, 0, 10)); 
formatting.Ranges.Add(XlCellRange.FromLTRB(2, 0, 2, 10));
// Create the default three-color scale rule to differentiate low, medium and high values in cell ranges.
XlCondFmtRuleColorScale rule = new XlCondFmtRuleColorScale();
formatting.Rules.Add(rule);
// Add the specified format options to the worksheet collection of conditional formats.
sheet.ConditionalFormattings.Add(formatting);

// Create an instance of the XlConditionalFormatting class. 
formatting = new XlConditionalFormatting();
// Specify cell ranges to which the conditional formatting rule should be applied (B1:B11 and D1:D11).
formatting.Ranges.Add(XlCellRange.FromLTRB(1, 0, 1, 10));
formatting.Ranges.Add(XlCellRange.FromLTRB(3, 0, 3, 10));
// Create the two-color scale rule to differentiate low and high values in cell ranges. 
rule = new XlCondFmtRuleColorScale();
rule.ColorScaleType = XlCondFmtColorScaleType.ColorScale2;
// Set a color corresponding to the minimum value in the cell range.
rule.MinColor = XlColor.FromTheme(XlThemeColor.Light1, 0.0);
// Set a color corresponding to the maximum value in the cell range.
rule.MaxColor = XlColor.FromTheme(XlThemeColor.Accent1, 0.5);
formatting.Rules.Add(rule);
// Add the specified format options to the worksheet collection of conditional formats.
sheet.ConditionalFormattings.Add(formatting);

' Create an instance of the XlConditionalFormatting class. 
Dim formatting As New XlConditionalFormatting()
' Specify cell ranges to which the conditional formatting rule should be applied (A1:A11 and C1:C11).
formatting.Ranges.Add(XlCellRange.FromLTRB(0, 0, 0, 10))
formatting.Ranges.Add(XlCellRange.FromLTRB(2, 0, 2, 10))
' Create the default three-color scale rule to differentiate low, medium and high values in cell ranges.
Dim rule As New XlCondFmtRuleColorScale()
formatting.Rules.Add(rule)
' Add the specified format options to the worksheet collection of conditional formats.
sheet.ConditionalFormattings.Add(formatting)

' Create an instance of the XlConditionalFormatting class. 
formatting = New XlConditionalFormatting()
' Specify cell ranges to which the conditional formatting rule should be applied (B1:B11 and D1:D11).
formatting.Ranges.Add(XlCellRange.FromLTRB(1, 0, 1, 10))
formatting.Ranges.Add(XlCellRange.FromLTRB(3, 0, 3, 10))
' Create the two-color scale rule to differentiate low and high values in cell ranges. 
rule = New XlCondFmtRuleColorScale()
rule.ColorScaleType = XlCondFmtColorScaleType.ColorScale2
' Set a color corresponding to the minimum value in the cell range.
rule.MinColor = XlColor.FromTheme(XlThemeColor.Light1, 0.0)
' Set a color corresponding to the maximum value in the cell range.
rule.MaxColor = XlColor.FromTheme(XlThemeColor.Accent1, 0.5)
formatting.Rules.Add(rule)
' Add the specified format options to the worksheet collection of conditional formats.
sheet.ConditionalFormattings.Add(formatting)