Ways to exit a loop in TypeScript

Question

Ways to exit a loop in TypeScript

I've encountered an issue with the following code where I am struggling to break the loop under certain conditions.

Desired Outcome: An error message should display, allowing the user to close it and remove the escalation node correctly.

Actual Outcome: The user is unable to manually dismiss the error message by clicking 'ok'; it disappears on its own after a few minutes.

public findVerticesBelow(vertexId: number) {
    // debugger
    this.recussionTime++;
    if(this.recussionTime <= 150){
        console.log(this.recussionTime)
        if (!this.vertexIdList.includes(vertexId)) {
            this.vertexIdList.push(vertexId)
          }
          let tempvertexIdList: Array<number> = new Array<number>();
          this.edges.forEach(edge => {
            if (edge.fromId == vertexId) {
              tempvertexIdList.push(edge.toId);
            }
          })

          tempvertexIdList.forEach(tempvertexId => {
            this.findVerticesBelow(tempvertexId)
          });
    }else{
        // debugger
        console.log("AAAAAAAAAAAAAAA")
        // alert("You are having a recursive loop please remove it before trying to remove nodes")
        // alert("ASCDFVGBHN")
    }
}

My goal is to terminate the loop and return a boolean value, but my current attempts have been unsuccessful. Can anyone offer assistance?

angular typescript

Answer 1

Answer №1

This may not be the most conventional approach, but it can still get the job done.

let numbers = [1, 2, 3, 3, 4, 4, 4];
try{
   numbers.forEach((num, index) => {
    console.log(num);
    if(num == 4){
       throw "break";
    }
   })
}catch(error){
console.log(error);
}

Answer 2

This may not be the most conventional approach, but it can still get the job done.

let numbers = [1, 2, 3, 3, 4, 4, 4];
try{
   numbers.forEach((num, index) => {
    console.log(num);
    if(num == 4){
       throw "break";
    }
   })
}catch(error){
console.log(error);
}

Answer 3

Answer №2

In both JavaScript and TypeScript files, it is not possible to stop the forEach loop. If you need to break out of a loop, consider using the for loop instead. For further insights, click here!

Answer 4

In both JavaScript and TypeScript files, it is not possible to stop the forEach loop. If you need to break out of a loop, consider using the for loop instead. For further insights, click here!

Answer 5

Answer №3

Breaking out of a forEach loop is not straightforward. Consider using a for loop instead.

Here are three lesser-known facts about the forEach loop:

The "return" keyword does not halt the iteration.
You cannot use "break" to exit prematurely.
"continue" cannot be used to skip iterations.

For more information, check out: https://medium.com/front-end-weekly/3-things-you-didnt-know-about-the-foreach-loop-in-js-ff02cec465b1

Alternatively,

You can utilize Array.every() to return false and terminate the loop when needed.

If you need to return true, consider using Array.some()

Answer 6

Breaking out of a forEach loop is not straightforward. Consider using a for loop instead.

Here are three lesser-known facts about the forEach loop:

The "return" keyword does not halt the iteration.
You cannot use "break" to exit prematurely.
"continue" cannot be used to skip iterations.

For more information, check out: https://medium.com/front-end-weekly/3-things-you-didnt-know-about-the-foreach-loop-in-js-ff02cec465b1

Alternatively,

You can utilize Array.every() to return false and terminate the loop when needed.

If you need to return true, consider using Array.some()

Ways to exit a loop in TypeScript

Answer №1

Answer №2

Answer №3

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