how to pass json data in curl command code example

Example 1: curl post json object command

curl -H "Accept: application/json" -H "Content-type: application/json" -X POST -d '{"id":100}' http://localhost/api/postJsonReader.do

Example 2: curl pass data in request

curl -d "param1=value1¶m2=value2" -X POST http://localhost:3000/data