Please explain break and continue on Objective-C

Question

First excuse my newbie question. I am learning Objective C and very new to programming itself.

Can you guys explain me what causes a break or continue inside a loop?

For example, what is the difference between the two codes?

 for (int i=0; i<100; i++) {
      if ([self okToProceed]) {
         [self doSomething];
      } else {
         break;
      }
  }

and

  for (int i=0; i<100; i++) {
      if ([self okToProceed]) {
         [self doSomething];
      } else {
         continue;
      }
  }

Will the first code stop the loop the first time okToProceed returns false and the second loop simply continue to run, but doing nothing when okToProceed is false?

Answer 1

A break statement exits the loop.
You can think of it as a means to create loop exit conditions.

For example, in your code: for(int i=0; i<100; i++), i<100 is a loop condition.
i.e. loop will exit if this condition is not met.

Similarly, inside if you have something like if(i == 34) { break; }.
This will exit the loop when value of i reaches 34 even though the loop exit condition specified was i<100.

---

A continue statement is used to skip to the next loop cycle.
This statement is used to basically avoid running the rest of the code within the loop.

Example:

for(i=0; i<5; i++) {
   if(i == 3) {
      continue;
   }
   print(i);
}

This loop will print 0 1 2 4.
When i will be 3, continue will skip to the next loop iteration and the statements after continue (i.e. print(i); will not execute).
Ofcourse, the loop condition is checked before the loop runs.