How to send a parameter which is dictionary in Postman

You could send data as raw body with the Content-Type application/json, this way it's up to you how the data is structured.

If for some reason you cannot send it with json, here is how we send dictionaries in the form:

object[ptype], object[mtype], object[dtype], object[category], object[city]

If you want to send it in the application/json format then the body should look like this:

{
    "key1":"value1",
    "key2":"value2"
}

For a comprehensive resource on how to serialise JSON go to http://www.newtonsoft.com/json/help/html/SerializingCollections.htm

You can do it with this:

POST Request in Postman:

Content-Type: Json/Application

{
   "IsManual":true,
   "platform":"IOS",
   "barcodeList":{"1":"DSSDsdsdsas","2":"DSSDsdsdsas"},
   "Client":"Cliente1",
   "ScanDate":"2018-10-16T17:03:02.2347052-03:00"
}