Subscribe to account events
You can call the event.account
operation to subscribe to account events.
Request parameters
The following parameters are encapsulated and passed in as an object.
Name | Required | Type | Description |
---|---|---|---|
to | true | string | The target account. |
Examples
// Create an event instance
const contractEvent = chain.event.contract({
to: 'first'
}, (err, data) => {
console.log(data)
})
// Register the event callback
contractEvent.on((err, data) => {
console.log(data)
})
// Update the contract code
chain.ctr.contract('first').update(bytecode, {}, (err, contract, data) => {})
Cancel the subscription of account events
You can call the accountEvent.close
operation to cancel the subscription of account events. This operation does not require any request parameters.
Examples
// Create an event instance
const accountEvent = chain.event.account({
to: 'Tester001'
}, (err, data) => {
console.log(data)
})
// Cancel the event
accountEvent.close((err, data) => {
console.log(data)
})
Subscribe to contract events
You can call the event.contract
operation to subscribe to contract events.
Request parameters
The following parameters are encapsulated and passed in as an object.
Name | Required | Type | Description |
---|---|---|---|
to | true | string | The hash or name of the target contract. |
Examples
// Create an event instance
const contractEvent = chain.event.contract({
to: 'first'
}, (err, data) => {
console.log(data)
})
// Register the event callback
contractEvent.on((err, data) => {
console.log(data)
})
// Update the contract code
chain.ctr.UpdateContract({
to: 'first',
data: {
code: bytecode
}
}, (err, data, rlpData) => {})
Unsubscribe contract events
You can call the contractEvent.close
operation to unsubscribe account events. This operation does not require any request parameters.
Examples
// Create an event instance
const contractEvent = chain.event.contract({
to: 'first'
}, (err, data) => {
console.log(data)
})
// Unsubscribe the event
contractEvent.close((err, data) => {
console.log(data)
})
Subscribe to topic events
You can call the event.topic
operation to subscribe to topic events.
Request parameters
The following parameters are encapsulated and passed in as an object.
Name | Required | Type | Description |
---|---|---|---|
to | true | string | The target topic. |
Examples
// Create an event instance
const topicEvent = chain.event.topic({
to: 'create_account'
}, (err, data) => {
console.log(data)
})
// Register the event callback
topicEvent.on((err, data) => {
console.log(data)
})
// Run CreateAccount to trigger the create_account topic event
chain.ctr.CreateAccount({
from: 'Tester001',
to: 'Tester002',
data: {
recover_key: '0xf5e50510a04a3f659a0e89f2063f79f8c1aed5ddaab6420ac47700020d9889dc14dae4dc9843c88d8222167095d9e6ce052e8a19cbc737c3f3cddf66409dbb0a',
auth_key: '0xf5e50510a04a3f659a0e89f2063f79f8c1aed5ddaab6420ac47700020d9889dc14dae4dc9843c88d8222167095d9e6ce052e8a19cbc737c3f3cddf66409dbb0a',
auth_weight: 100
}
}, (err, data) => {})
Unsubscribe topic events
You can call the topicEvent.close
operation to unsubscribe topic events. This operation does not require any request parameters.
Examples
// Create an event instance
const topicEvent = chain.event.topic({
to: 'create_account'
}, (err, data) => {
console.log(data)
})
// Unsubscribe the event
topicEvent.close((err, data) => {
console.log(data)
})
Subscribe to block events
You can call the event.block
operation to subscribe to contract events. This operation requires no request parameters.
Examples
// Create an event instance
const blockEvent = chain.event.block({}, (err, data) => {
console.log(data)
})
// Register the event callback to trigger the event while generating the block
blockEvent.on((err, data) => {
console.log(data)
})
Unsubscribe block events
You can call the blockEvent.close
operation to unsubscribe topic events. This operation does not require any request parameters.
Examples
// Create an event instance
const blockEvent = chain.event.block({}, (err, data) => {
console.log(data)
})
// Unsubscribe the event
blockEvent.close((err, data) => {
console.log(data)
})