How to send bitcoin programatically using API? Bitcoin Transaction. (Without Setting Node) Want to send BTC from one address to another address without using
  JSON-RPC.


Followed and used:


https://bitcore.io/api/
https://www.npmjs.com/package/bitcoin-transaction/v/1.1.1


2nd:bitcoin-transaction Working good for testnet but giving each time new errors for Mainnet.

If anyone knows better way to send BTC, kindly let me know.
From C#, I would use NBitcoin to generate raw transaction and push it to some API provider. This eliminates the need of setting up full node.