If you choose to use an expression condition, define a text expression that returns a boolean value. The returned value determines whether formatting is applied. The configuration panel is shown below.

field.field is used to select the type of condition.
Expression.This field is used to define an expression that should return a boolean value.
for example,C#Suitable formula:
Customers.CustomerName == “MyCustomer”
The report generator cannot render conditional formatting if the expression cannot return a boolean value.
important:The expression must return a boolean value. Otherwise the conditional formatting will fail.