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Tyler McDonald
Full Stack JavaScript Techdegree Graduate 16,700 PointsWhy must we use an arrow function for onClick?
Why can't we just do this: onClick={ props.changeScore(-1) } instead of this onClick={ () => props.changeScore(-1) }
1 Answer
Steven Parker
231,236 PointsIf you define a function, it will be performed later when the event occurs. Otherwise, the code will be performed now and the results will be assigned where a function is expected; and the error will not be detected until the event occurs.
Tyler McDonald
Full Stack JavaScript Techdegree Graduate 16,700 PointsTyler McDonald
Full Stack JavaScript Techdegree Graduate 16,700 PointsThat makes sense. So would it be similar to trying something like this?
document.querySelector('#element').addEventListener(myFunction(1))Steven Parker
231,236 PointsSteven Parker
231,236 PointsThat code would call "myFunction" now instead of passing a reference to it for the listener to call later.