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Given a primitive value age I know how to create an expression like this: //assuming: age is an int or some other primitive type employee => employee.Age == age By doing this: var entityType = typeof(Employee); var propertyName = "Age"; int age = 30; var parameter = Expression.Parameter(entityType, "entity"); var lambda = Expression.Lambda( Expression.Equal( Expression.Property(parameter, propertyName), Expression.Constant(age) ) , parameter); That works fine except in scenarios where the property and constant in question are not primitive types. How would I construct a similar expression if the comparison is between objects? With EF I can just write: Location location = GetCurrentLocation(); employees = DataContext.Employees.Where(e => e.Location == location); That also works , but if I try to create the same expression: var entityType = typeof(Employee); var propertyName = "Location"; var location = GetCurrentLocation(); var parameter = Expression.Parameter(entityType, "entity"); var lambda = Expression.Lambda( Expression.Equal( Expression.Property(parameter, propertyName), Expression.Constant(location) ) , parameter); I get an error that says: Unable to create a constant value of type 'Location'. Only primitive types or enumeration types are supported in this context. My suspicion is that Expression.Constant() only expects primitive types, so I need to use a different expression factory method. (maype Expression.Object ? - I know that doesn't exist) Is there a way to create an expression that compares objects? Why is that EF is able to interpret it correctly if its a compiled LINQ stateme

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