Before we learn about the differences of the setinterval and settimeout, we need to understand some properties which are common for both the type of functions and this will help us analyze on why there is a confusion among developers about the usage of the functions for which this article has been articulated!
Both these concepts have unique use-cases for which they are built, and it is the use cases that set these 2 functions apart in different genres. In terms of execution, settimeout gets executed only ONCE after the specified time out period has elapsed whereas setinterval gets executed in a repeated manner after the specified time period as per the argument is elapsed. The two functions’ use case in a real-life analogy is a one-off meeting for settimeout function versus a recurrence meeting or a morning hurdle that takes place as a part of the agile process. The syntax of both the functions are strikingly different and can judge as a place of difference as the command call will determine which function needs to be executed.
In order to stop the execution of the functions, there are respective function calls that must be made and can NOT be interchanged in any scenario. For stopping a function that has run from settimeout, one would need to call clearTimeout to clear off the execution of settimeout variable whereas for setinterval one would need to call the clearInterval function in order to perform a similar functionality for setinterval. Now, in order to achieve the usability of the other function, it is somehow possible to use a nested settimeout wherein we run the settimeout function in a loop and run it for a specified duration or number of times as per the requirement in order to achieve somehow closer to the setinterval function. Just for everyone to note that nested settimeout function’s stop-watch will start after the function has been executed whereas setinterval function’s stop-watch starts from the time moment the setinterval is executed. In other words, there might be cases, that if the function takes more time to execute than the time specified to setinterval, there are chances of overflow, but with nested settimeout this case will never be possible. Last but not the least, the concept of zero delay schedule is only applicable for settimeout and not for setinterval.
|When does this execute||This function executes only once after the specified time interval has elapsed||This function executes repeatedly after every elapsing of the specified time interval|
|Analogy to real-life scenario:||This is like a one-off meeting in our outlook calendars||This is like a recurrence meeting that is set up with the team every morning as a part of the agile process.|
|Frequency of occurrence:||This function allows execution of the set of codes that is passed as an argument to the function only ONCE.||The function allows the set of codes that is passed as an argument to be run multiple times till the command is given to be stopped.|
|Syntax that leads to the utility:||setTimeout(< Function or code >, < delay in ms >, [argument 1], [argument
|setInterval(< Function or code >, < delay in ms >, [argument 1], [argument
|How to clear the execution of respective functions:||To stop the execution of the command when the respective command is already executed, we invoke the stopping function known as clearTimeout, and the variable returned by the setTimeout needs to be passed as an argument.||To stop the execution of the command when the respective command is already executed, we invoke the stopping function known as clearInterval, and the variable returned by the setInterval needs to be passed as an argument.|
|Possible to achieve the other utility?||By using a special form of the setTimeout function it is possible to recreate a similar utility as that of the setInterval only with a slight variation as discussed in our other section in this article.||With none of the methods available it is possible to recreate anything fairly closely similar to the utility of the setTimeout usability.|
|Zero delay scheduling||This methodology is passing 0 ms as a timeout interval so that the function call is scheduled as soon as possible but only after the execution of the current script.||The concept of zero delays will not make any sense for setInterval command as the set of codes will be executing repeatedly after 0 ms which means that virtually it will be an infinite loop.|