Solution : TypeError: Cannot read properties of undefined (reading 'map')

 Hello, today I will try to share about Solution : TypeError: Cannot read properties of undefined (reading 'map') , ok lets break it out.

Let see piece of code the following :

 {this.state.stateShowQuestionAndAnswer['answers']?.map((name:any) => (

          <li>{name}</li>

        ))}

above code will generate error in Nextjs like below :

Solved it by first asking if the array existed.

add sign ? code

like scripts below :

        {this.state.stateShowQuestionAndAnswer['answers']?.map((name:any) => (

          <li>{name}</li>

        ))}

Hope this information can helping you.