Analysis of setInterval and setTimeout examples in JS

This article mainly shares with you the analysis of setInterval and setTimeout examples in JS, hoping to help everyone.

1 setInterval

is a function. Function: You can repeatedly execute a certain code block (function)
setInterval(function, time interval), how long to execute the first parameter (function block) repeatedly
Note: Time unit millisecond 1000 = 1 second
Function names cannot be written in parentheses. This way of writing is wrong: fn()

2 clearInterval clear timer (setInterval)

 注意：  在开启一个新的定时器之前，先清除定时器

3 chrome new tab page plug-in
Infinity new tab page

4 aLi is a class array. When setting the style in a loop, be careful to use a for loop instead of for in

5 The syntax structure of setTimeout is similar to setInterval, but the meaning is different.
setTimeout waits for how long to execute a certain code block, similar to timing*
setTimeout(fn, 3000), wait until 3 seconds later to execute the fn function Timing*
setInterval(fn, 3000), execute the fn function every 3 seconds Engine

6 Recursive function
A function can call other functions or itself. This kind of function is called a recursive function
Note: Recursive function has two meanings: progression and regression
Application scenarios of recursive functions: A large problem can be split into multiple similar sub-problems, and the solutions to these sub-problems are similar,
At this time, you can use the recursive function,
For example: consider this requirement: printing 1-3 in the body as a big problem
Sub-problem: Play a number each time, solution, document.write()

Recursively create folders, recursively delete folders

Note: When writing recursive functions, pay attention to the exit. Set exit conditions for recursive calls

7 Clear timer
setInterval Execute a piece of code (loop) every certain time Clear: clearInterval
setTimeout Wait until a certain amount of time to execute a piece of code ( Execute once) clear: clearTimeout

1 setInterval
Is a function, function: can repeatedly execute a certain code block (function)
setInterval(function, time interval), how long to execute the first parameter (function block) repeatedly
Note: Time unit millisecond 1000 = 1 second
Function names cannot be written in parentheses. This way of writing is wrong: fn()

2 clearInterval clear timer (setInterval)

 注意：  在开启一个新的定时器之前，先清除定时器

3 chrome new tab page plug-in
Infinity new tab page

4 aLi is a class array. When setting the style in a loop, be careful to use a for loop instead of for in

5 The syntax structure of setTimeout is similar to setInterval, but the meaning is different.
setTimeout waits for how long to execute a certain code block, similar to timing*
setTimeout(fn, 3000), wait until 3 seconds later to execute the fn function Timing*
setInterval(fn, 3000), execute the fn function every 3 seconds Engine

6 Recursive function
A function can call other functions or itself. This kind of function is called a recursive function
Note: Recursive function has two meanings: progression and regression
Application scenarios of recursive functions: A large problem can be split into multiple similar sub-problems, and the solutions to these sub-problems are similar,
At this time, you can use the recursive function,
For example: consider this requirement: printing 1-3 in the body as a big problem
Sub-problem: Play a number each time, solution, document.write()

Recursively create folders, recursively delete folders

Note: When writing recursive functions, pay attention to the exit. Set exit conditions for recursive calls

7 Clear timer
setInterval Execute a piece of code (loop) every certain time Clear: clearInterval
setTimeout Wait until a certain amount of time to execute a piece of code ( Execute once) Clear: clearTimeout

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