Question 272776 in Javascript Question posted in
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Javascript: Printing the statement line by line when we have a setTimeout

We have 5 statements in a line and If we have a set timeout in the 3 statement it will executed after all the remaining statement got executed. I’m looking to execute the each statement line by line even If we have a set timeout in-between the code.

Example:
We have some statements

console.log("A");
setTimeout(console.log("B"), 1000);
console.log("C");

The expected output is A C B but I want to print is a A B C.
Any thoughts on this?

Tags:

2

Answers


  1. 0

    I assumed your setTimout was incorrect since it WILL execute the console.log immediately.

    To do what you want, you need to replace console and setTimeout

    const myMessages = [];
const myConsole = window.console;
window.console = { log: (str) => myMessages.push(`mine: ${str}`) }
const myTimeout = window.setTimeout;
window.setTimeout = func => {
  myMessages.push(func)
};
console.log("A");
setTimeout(() => console.log("B"), 1000);
console.log("C");
window.console = myConsole; // reset
myMessages.forEach(msg => {
  if (typeof msg === "string") console.log(msg)
  else msg()
})
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  2. 0

    you need to chain the timeouts, something like this (treat this as a proof of concept, but it is tested)

    <script>
var linesToPrint = ['A', 'B', 'C'];
function WriteNextLine(lineCount)
{   if (linesToPrint[lineCount] != undefined)
    {   console.log(linesToPrint[lineCount]);
        setTimeout(function(){WriteNextLine(++lineCount);}, 1000);
    }
}
WriteNextLine(0);
</script>
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