Sets the user variable in the event context associated with the key. It returns
false if the event context does not exist or the result of evaluating the variable name expression is
null, and returns
true if the variable setting is successful.
- Topic of the event context.
- Unique key that distinguishes the event context
- User variable
- Expression that returns the value to be assigned to a variable
Use the sessionkey field value as the identifier of the
web_session context and set the
client_ip variable as an ip field value.
evtctxsetvar("web_session", sessionkey, "client_ip", ip)