Hi Yacinus,
Attached is the sample which helps you to change the background color and value of the cells which hold the comparison result of the Expression fields.
http://websamples.syncfusion.com/samples/Grid.Web/5.1.0.51/Forum-64151-1/main.htm'OnQueryCellStyleInfo' event is used to check the result of expression fields and change the column accordingly.
In the sample when the result of the expression field is false, the value '0' is checked and the celltext has been changed to 'False' and the background color to red.
If the result of the expression field is true, the value '1' is checked and the celltext has been changed to 'True' and the background color to green.
Please let us know if you have any other queries.
Regards,
Valli