beforeValueChange

Most components in ReactiveSearch provides a beforeValueChange prop. It is a callback function which accepts component's future value as a parameter and returns a promise. It is called everytime before a component's value changes. The promise, if and when resolved, triggers the execution of the component's query and if rejected, kills the query execution. This method can act as a gatekeeper for query execution, since it only executes the query after the provided promise has been resolved.

Note:

If you're using Reactivesearch version >= 1.1.0, beforeValueChange can also be defined as a synchronous function. value is updated by default, unless you throw an Error to reject the update. For example with search-box:

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beforeValueChange = value => {
	// The update is accepted by default
	if (value && value.toLowerCase().contains('Social')) {
        // To reject the update, throw an error
        throw Error('Search value should not contain social.');
	}
};

Note

Most of the time your needs can be solved using value-change event. If you absolutely need beforeValueChange you should ensure that you don't pass a function which takes a very long time to resolve the promise. The component goes in a locked state when using beforeValueChange and before the promise is resolved. This means all the state updates are suspended for the component.