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JavaScript Understanding "this" in JavaScript

Sheila Babadi
Sheila Babadi
5,241 Points

this.name and this.state

I don't quite understand why it's necessary and/or better to use this.name and this.state in the function printMyCityAndState (or whatever it was called). If it were just "name" and "state", wouldn't the correct values still be printed if you were calling it on a specific instance of that object?

P.S. You forgot the Portland Thorns!!!

1 Answer

Steven Parker
Steven Parker
228,978 Points

Remember that the method is being defined inside the constructor for City.

Inside the constructor, the names "city" and "state" refer to the arguments passed to the constructor, not to the instance variables they get assigned to. So to make sure the method uses the instance variables, the variable names must be prefixed with "this.". Also, the contents might be different if the arguments were undefined when the constructor was called.