Content-type in curl code example

Example 1: curl https post

curl -d "" https://example.com

curl -H "Content-Type: application/json" --data "@C:\Users\xxx\Desktop\body.json" https://example.com/api/service

Example 2: curl pass data in request

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