Cannot seem to correctly change the value of a variable from a prompt

Question

Was experimenting with what i learned from this lesson by trying to do something myself but I am struggling.  here is my code, i think you will understand what I have been trying to do,
var score = 0;                                   
score += 10, score +=5;                                        
var bonusPoints = 0;                                               
bonusPoints += prompt("input desired bonus points");                                           
score += bonusPoints;                                     
alert(score);                                            
however it keeps adding whatever is input in the prompt as a string at the end of the score value. Any help is greatly appreciated, many thanks :)

Austin Whipple · Accepted Answer

Hi Forrest,
By default, the value submitted to the prompt you're displaying is going to be stored as a string. Using += is going to produce strange results using anything that's not an integer. Luckily, JavaScript has some handy functions to convert strings to integers/numbers! I suspect you can use parseint() without much problem, but perhaps Number() would work as well. Here's a StackOverflow article with lots more information (https://stackoverflow.com/questions/1133770/how-to-convert-a-string-to-an-integer-in-javascript).

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Forrest Pollard

Forrest Pollard

Cannot seem to correctly change the value of a variable from a prompt

1 Answer

Austin Whipple

Austin Whipple