How to pass a parameter to an event handler or callback?
Interviewer Expectations for this Question
01
Core Competency
Assesses fundamental understanding of React conventions, runtime behavior, and memory/performance considerations.
02
Evaluation Criteria
Hiring managers look for precision, avoidance of ambiguous jargon, and ability to explain trade-offs under real production conditions.
Comprehensive Model Answer
Verified Solution
You can use an _arrow function_ to wrap around an _event handler_ and pass parameters:
```jsx harmony
<button onClick={() => this.handleClick(id)} />
This is an equivalent to calling `.bind`:
<button onClick={this.handleClick.bind(this, id)} />
Apart from these two approaches, you can also pass arguments to a function which is defined as arrow function
<button onClick={this.handleClick(id)} />;
handleClick = (id) => () => {
console.log("Hello, your ticket number is", id);
};
```
Candidate Response Strategy & Interview Tips
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- Discuss complexity & edge cases: Proactively explain time/space complexity or boundary conditions (null values, scale limits).
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