TypeScript - setInterval() function example
In this article, we would like to show you how to use setInterval() in TypeScript.
Quick solution:
xxxxxxxxxxsetInterval((): void => { console.log('This will be displayed every 1000ms (1s).');}, 1000);or:
xxxxxxxxxxconst handle = setInterval((): void => { console.log('This will be displayed every 1000ms (1s).');}, 1000);clearInterval(handle); // stops intervals
| Syntax |
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| Parameters | callback - function called every indicated time (interval),delay - optional interval time as an integer number (in milliseconds),arg1, arg2, arg3, ... - optional arguments passed as callback arguments. |
| Result | Created interval handle (as integer number). |
| Description |
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Below we present some practical examples for better understanding.
In this example, we create and call a simple function that displays some text every second.
Runnable example:
xxxxxxxxxxsetInterval((): void => { console.log('This will be displayed every 1000ms (1s).');}, 1000);In this example, we create a function with setInterval that counts to 5 every second.
Runnable example:
xxxxxxxxxxlet i = 0;const interval = setInterval((): void => { console.log(i + 1); if (++i === 5) { clearInterval(interval); }}, 1000);In this example, we create customSetInterval that takes in three arguments:
count- how many times we want to call thecallbackfunction,delay- time betweencallbackfunction calls,callback- a function to be called.
Runnable example:
xxxxxxxxxxconst customSetInterval = (count: number, delay: number, callback: (i: number, count: number) => void): void => { let i = 0; const interval = setInterval(() => { callback(i, count); if (++i === count) { clearInterval(interval); } }, delay);};// Usage example:const foo = (index: number, count: number): void => console.log(`${index + 1}/${count} Some text here ...`);customSetInterval(5, 1000, foo);Output (one line every second):
xxxxxxxxxx1/5 Some text here ...2/5 Some text here ...3/5 Some text here ...4/5 Some text here ...5/5 Some text here ...