OptionalcomponentOptionalcomponentOptionalcomponentOptionalcomponentCalled immediately before mounting occurs, and before Component.render. Avoid introducing any side-effects or subscriptions in this method.
Note: the presence of getSnapshotBeforeUpdate or StaticLifecycle.getDerivedStateFromProps getDerivedStateFromProps prevents this from being invoked.
16.3, use componentDidMount or the constructor instead; will stop working in React 17
OptionalcomponentCalled when the component may be receiving new props. React may call this even if props have not changed, so be sure to compare new and existing props if you only want to handle changes.
Calling Component.setState generally does not trigger this method.
Note: the presence of getSnapshotBeforeUpdate or StaticLifecycle.getDerivedStateFromProps getDerivedStateFromProps prevents this from being invoked.
16.3, use static StaticLifecycle.getDerivedStateFromProps getDerivedStateFromProps instead; will stop working in React 17
OptionalcomponentOptionalcomponentCalled immediately before rendering when new props or state is received. Not called for the initial render.
Note: You cannot call Component.setState here.
Note: the presence of getSnapshotBeforeUpdate or StaticLifecycle.getDerivedStateFromProps getDerivedStateFromProps prevents this from being invoked.
OptionalgetRuns before React applies the result of render to the document, and returns an object to be given to componentDidUpdate. Useful for saving things such as scroll position before render causes changes to it.
Note: the presence of this method prevents any of the deprecated lifecycle events from running.
OptionalshouldCalled to determine whether the change in props and state should trigger a re-render.
Component always returns true.
PureComponent implements a shallow comparison on props and state and returns true if any
props or states have changed.
If false is returned, Component.render, componentWillUpdate
and componentDidUpdate will not be called.
OptionalUNSAFE_Called immediately before mounting occurs, and before Component.render. Avoid introducing any side-effects or subscriptions in this method.
This method will not stop working in React 17.
Note: the presence of getSnapshotBeforeUpdate or StaticLifecycle.getDerivedStateFromProps getDerivedStateFromProps prevents this from being invoked.
16.3, use componentDidMount or the constructor instead
OptionalUNSAFE_Called when the component may be receiving new props. React may call this even if props have not changed, so be sure to compare new and existing props if you only want to handle changes.
Calling Component.setState generally does not trigger this method.
This method will not stop working in React 17.
Note: the presence of getSnapshotBeforeUpdate or StaticLifecycle.getDerivedStateFromProps getDerivedStateFromProps prevents this from being invoked.
16.3, use static StaticLifecycle.getDerivedStateFromProps getDerivedStateFromProps instead
OptionalUNSAFE_Called immediately before rendering when new props or state is received. Not called for the initial render.
Note: You cannot call Component.setState here.
This method will not stop working in React 17.
Note: the presence of getSnapshotBeforeUpdate or StaticLifecycle.getDerivedStateFromProps getDerivedStateFromProps prevents this from being invoked.
Catches exceptions generated in descendant components. Unhandled exceptions will cause the entire component tree to unmount.