How to use expression as the variable name or as a node in json format in logic apps

Question

We are trying to send a data to third party service.

To send the data we follow the specific json format but in the format one of the field is as shown below

"@number" : "value(user-defined)",

This particular field is throwing the error can anyone please comment on how to clear out his error as the name of the field should be same, if not it throws error as "@number" field is missing when HTTP request is sent.

Thanks in advance

Answer 1

The @ sign is a reserved character in LogicApps expressions. If you look at the code view, any expression you use starts with that character, hence why it's reserved and hence why it spits the dummy when you try and use it as the first character in any property name.

I find that the easiest way to overcome this is to create a string variable that contains your object and then use the json() expression to turn it into an object and send that into your HTTP call.

Of course you should be able to skip the Compose step and simply use the expression directly in the body of your HTTP call. I just used that for illustration purposes.

Flow

The expression in the second step is ... json(variables('My String'))

Result