let sessionId; //Exists in the public zone, and can be conveniently used at any time

// Monitors inbound call events
window.tccc.on(window.tccc.events.callIn, (response) => {
 // Triggered when a session calls in, and stores this session's sessionId in a public zone
  sessionId = response.data.sessionId;
})

// Implements the answering method
function accept() {
  if (sessionId) {
    window.tccc.Call.accept({ sessionId })
      .then(() => {
        // Successfully answers and starts the call
      })
      .catch(err => {
        // Failed to answer, and displays detailed error reason
        const error = err.errorMsg;
      })
  } else {
    console.error('The session to be answered was not found');
  }
}

// Then, accept() can be executed at the required place to trigger answering the call

window.tccc.on(window.tccc.events.callIn, (response) => {
  // Triggered when session calls in
})
window.tccc.on(window.tccc.events.userAccessed, (response) => {
  // Agent connection
})
window.tccc.on(window.tccc.events.sessionEnded, (response) => {
  // Triggered when session ends
})