Python - How To Stop a for Loop in Python

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This article introduces different methods to stop a for loop in Python.

Use a break Statement to Stop a Python for Loop

Use a break statement to stop a for loop in Python.

For example,

max=4 counter=0 for a in range(max):    if counter==3:          print("counter value=3. Stop the for loop")          break              else:       print("counter value<3. Continue the for loop. Counter value=",counter)       counter=counter+1       continue    break 

Output:

counter value<3. Continue the for loop. Counter value= 0 counter value<3. Continue the for loop. Counter value= 1 counter value<3. Continue the for loop. Counter value= 2 counter value=3. Stop the for loop 

Here, as long as the for loop criteria is met, the following print statement is printed. For example -

counter value<3. Continue the for loop. Counter value= 0 

However, once the counter value is equal to 3, it breaks out of the for loop. Hence, the for loop stops.

Wrap the Code in a Function, and Then Use the return Statement

Wrap the code in a function, and then use the return statement.

For example,

def fncreturn():    return;   max=4 counter=0 for a in range(max):    if counter==3:          print("counter value=3. Stop the for loop")          fncreturn()             else:       print("counter value<3. Continue the for loop. Counter value=",counter)       counter=counter+1       continue    break 

Output:

counter value<3. Continue the for loop. Counter value= 0 counter value<3. Continue the for loop. Counter value= 1 counter value<3. Continue the for loop. Counter value= 2 counter value=3. Stop the for loop 

Here, when the counter value reaches to 3, the function is called. The function has just a return statement. Post that, it helps exit from the for loop.

Raise an Exception to Stop a Python for Loop

Raise an exception to stop a for loop.

For example,

max=4 counter=0 try:     for a in range(max):        if counter==3:          print("counter value=3. Stop the for loop")          raise StopIteration           else:           print("counter value<3. Continue the for loop. Counter value=",counter)           counter=counter+1        except StopIteration:    pass 

Output:

counter value<3. Continue the for loop. Counter value= 0 counter value<3. Continue the for loop. Counter value= 1 counter value<3. Continue the for loop. Counter value= 2 counter value=3. Stop the for loop 

Here, when the counter value reaches to 3, the exception is raised. Immediately it exits from the for loop.