We have added a expression "Some String: " & [COUNTYNAME] to a layer in mxd. I have published this mxd as a service and when I see the REST end point for this service, the "Display Field" shows "COUNTYNAME" and not the expression.
How can make the REST to display the expression?
FYI: I have restarted the services and cleared the REST cache.
The primary display field defaults to the first field of string type that contains the text "name" (case insensitive) in the field name. If no "name" field exists, the primary display field defaults to the first field of string type, then the first field of integer type, then the first field of any type. You can change the primary display field from the Fields tab of the Layer or Table Properties dialog box
Here is a similar help topic for a recent version:
Even without an expression, just setting the field name in the 'display expression' isn't picked up either. I did find that the 'value' was based upon the selected field. Seems strange
David, Glad you were able to identify the cause. In the upcoming 10.1 version, the REST cache will be automatically managed each time a service is updated, so this will not be an issue.
Just to clarify: when MapService sees a DisplayExpression, it uses the first field name used in that DisplayExpression. In your cases, your display expression ("Some String: " & [COUNTYNAME]) contains [COUNTYNAME] that's where [COUNTYNAME] is coming from...
