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sidni ahmed
3,329 Pointswhy use 'while' loop instead of 'for'?
why use 'while' loop instead of 'for'? is there a big difference?
2 Answers
Steve Hunter
57,712 PointsHi there,
A for loop runs for a pre-determined number of times. So, it can iterate through an array from start to finish, say, but it will only ever loop for that specific number.
A while loop will carry on until a pre-determined scenario takes place. That may happen immediately, or it may require a hundred iterations. So, the number of loops is governed by an outcome, not a number. For example, you can continue looping until the user presses the Z key (while keyPressed != 'Z') - the loop will constantly run until that happens. It may never happen.
A for loop has it's bounds set from the beginning and, yes, while you can manipulate those bounds, the general implementation is such that the maximum number of loops is pre-determined.
I hope that makes sense!
Steve.
sidni ahmed
3,329 Pointsthanks a lot guys!
Steve Hunter
57,712 PointsNo problem! :-)
Jacob Mishkin
23,117 PointsJacob Mishkin
23,117 Pointsin general a while loop is used if you want an action to repeat itself until a certain condition is met i.e. if statement. An for loop is used when you want to iterate through an object. i.e. iterate through an array.