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JavaScript React Basics (2018) Understanding State Understanding State Review

Charlie Prator
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Charlie Prator
Front End Web Development Techdegree Graduate 19,854 Points
Posted by Charlie Prator
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Charlie Prator
Front End Web Development Techdegree Graduate 19,854 Points

What does the exclamation point in this code stating?

confirmGuest = () => {
  this.setState( prevState => ({ 
    isConfirmed: !_________.isConfirmed
  }));
}

Is the above saying to update the state of isConfirmed through the negation of its previous state? So, if the previous state of isConfirmed is false, then we're changing it to true with the exclamation point, right?

1 Answer

Marie Franklin
Marie Franklin
13,358 Points

yes!... just toggling the value of isConfirmed

isConfirmed: !prevState.isConfirmed