curl post json

JavaScript
curl -d "user=user1&pass=abcd" -X POST https://example.com/logincurl -X POST -H "Content-Type: application/json" \
 -d '{"username":"abc","password":"abc"}' \
 https://api.example.com/v2/login
curl -d "" https://example.com

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

curl -X POST https://example.com/resource.cgi

curl --request POST https://example.com/resource.cgi
curl -H "Accept: application/json" -H "Content-type: application/json" -X POST -d '{"id":100}' http://localhost/api/postJsonReader.docurl -d '{"key1":"value1", "key2":"value2"}' -H "Content-Type: application/json" -X POST http://localhost:3000/data
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