Gradient Fill Effect

You can also add gradient effects to emphasize the comments blocks by applying fill-color and patterns.

Using Code

To add the gradient effects, use the Fill property of the IShapeBase interface.

fpSpread1.Features.EnhancedShapeEngine = true;
IWorksheet TestActiveSheet = fpSpread1.AsWorkbook().ActiveSheet;
IShape shape;
shape = TestActiveSheet.Cells["A1"].AddComment("InsetPen = false").Shape;
TestActiveSheet.Cells["A1"].Comment.Visible = true;
shape.Fill.OneColorGradient(GrapeCity.Spreadsheet.Drawing.GradientStyle.FromCenter, 1, 1);
shape.Fill.GradientStops.Delete(0);
shape.Fill.GradientStops.Delete(0);
shape.Fill.GradientStops.Delete(0);
shape.Fill.GradientStops.Insert(0xffff00, 0);
shape.Fill.GradientStops.Insert(0xffffff, 0.5);
shape.Fill.GradientStops.Insert(0x00ffff, 1);
shape.Fill.GradientStops[0].Color.SchemeColor = 23;
shape.Fill.PathShadeType = GrapeCity.Drawing.PathShadeType.Shape;
IShape aa = fpSpread1.AsWorkbook().ActiveSheet.Cells["A1"].Comment.Shape;

FpSpread1.Features.EnhancedShapeEngine = True
Dim shape As IShape
Dim TestActiveSheet As IWorksheet = FpSpread1.AsWorkbook().ActiveSheet
shape = TestActiveSheet.Cells("A1").AddComment("InsetPen = false").Shape
TestActiveSheet.Cells("A1").Comment.Visible = True
shape.Fill.OneColorGradient(GrapeCity.Spreadsheet.Drawing.GradientStyle.FromCenter, 1, 1)
shape.Fill.GradientStops.Delete(0)
shape.Fill.GradientStops.Delete(0)
shape.Fill.GradientStops.Delete(0)
shape.Fill.GradientStops.Insert(&Hffff00, 0)
shape.Fill.GradientStops.Insert(&HfffffF, 0.5)
shape.Fill.GradientStops.Insert(&H00fffF, 1)
shape.Fill.GradientStops(0).Color.SchemeColor = 23
shape.Fill.PathShadeType = GrapeCity.Drawing.PathShadeType.Shape
Dim aa As IShape = FpSpread1.AsWorkbook().ActiveSheet.Cells("A1").Comment.Shape

Using Runtime UI

 You can add or manipulate effects at run time via the Fill Effects dialog. The Fill Effects dialog provides options like colors, variants, shading styles, patterns, and a sample preview to view the used gradient effect.

To add an effect to a comment block, select the comment on the sheet at runtime and use the keyboard shortcut key combination "Ctrl+1". This will invoke the Format Comment dialog box. Navigate to Colors and Lines tab and select the Fill Effects option from the Color picker dropdown.  

Using Spread Designer

To view comments and add gradient effects to the block in the Spread Designer, follow below mentioned steps:

1. Set the EnhancedShapeEngine and ExcelCompatibleKeyboardShortcuts to true in the properties pane. 
2. Load the sheet that includes comments. 
3. Select the comment on which you want to add or modify the gradient effect. 
4. Right click the comment to view the context menu and select the Format Comment option. 
   
5. Navigate to Colors and Lines tab of the Format Comment dialog.
   
6. Select the Fill Effects button to open the Fill Effects dialog.