title: How to return json data to a react state?
body: <p>I have a react component that makes a <code>.post</code> to an express server (my own server). The server uses <code>web3</code> to sign a transaction on <code>Ethereum</code>. Once the transaction is included in a block, a <code>json</code> object is returned to the server. It looks like this:</p>
  
  <pre><code>{ blockHash: '0xcd08039bac40e2865886e8f707ce9b901978c339d3abb81516787b0357f53fbd',
    blockNumber: 4611028,
   ...other data...
    transactionHash: '0x12c65523743ed169c764553ed2e0fb2af1710bb20a41b390276ffc2d5923c6a9',
    transactionIndex: 1 }
  </code></pre>
  
  <p>I need to store the <code>transactionHash</code> into the state of the above component. I have been searching for 2 days and am probably missing something very obvious. </p>
  
  <p>Is this server-side or client-side code?
  Do I need to learn and use async because of the inherent time delay in talking to <code>Ethereum</code>?</p>
  
  <p>Any help is appreciated! </p>
  
  <p>Thanks</p>