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Is there any way I can set value of array in specific index with React imutability helper ?

For example something like this:

   const newState = update(this.state , {
        open[8]:{$set: false}
    })
    this.setState(newState);

or do I have to deep clone that array using JSON and then set new value at specific index and then use react imutability helper to update state?

Is there any way I can set value of array in specific index with React imutability helper ?

For example something like this:

   const newState = update(this.state , {
        open[8]:{$set: false}
    })
    this.setState(newState);

or do I have to deep clone that array using JSON and then set new value at specific index and then use react imutability helper to update state?

• javascript
• reactjs

Share Improve this question Follow asked Feb 23, 2017 at 16:48 ĽubomírĽubomír 1,21122 gold badges1313 silver badges2222 bronze badges 1

• You could use { open: state.open.filter((value, index) => index != 8) } – Aaron Beall Commented Feb 23, 2017 at 20:37

Add a ment  | 

1 Answer 1

Sorted by: Reset to default 7

Assuming your state has the following format:

{
  open: [
    true,
    false,
    true,
    ...
  ]
}

I believe this should work:

const newState = update(this.state , {
  open: {
    8: {$set: false}
  }
})

Is there any way I can set value of array in specific index with React imutability helper ?

For example something like this:

   const newState = update(this.state , {
        open[8]:{$set: false}
    })
    this.setState(newState);

or do I have to deep clone that array using JSON and then set new value at specific index and then use react imutability helper to update state?

Is there any way I can set value of array in specific index with React imutability helper ?

For example something like this:

   const newState = update(this.state , {
        open[8]:{$set: false}
    })
    this.setState(newState);

or do I have to deep clone that array using JSON and then set new value at specific index and then use react imutability helper to update state?

• javascript
• reactjs

Share Improve this question Follow asked Feb 23, 2017 at 16:48 ĽubomírĽubomír 1,21122 gold badges1313 silver badges2222 bronze badges 1

• You could use { open: state.open.filter((value, index) => index != 8) } – Aaron Beall Commented Feb 23, 2017 at 20:37

Add a ment  | 

1 Answer 1

Sorted by: Reset to default 7

Assuming your state has the following format:

{
  open: [
    true,
    false,
    true,
    ...
  ]
}

I believe this should work:

const newState = update(this.state , {
  open: {
    8: {$set: false}
  }
})

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