Error in displaying JSON in react

Question

On calling an API , got a response, stored it in a variable "items" and it is getting displayed on console also. When i access items.data[0].id, it is getting displayed in console but when i try to display same thing in render method, error is coming that :-

TypeError : cannot read property 0 of undefined.

I am calling the API call in ComponentWillMount() function in react.

You get that error because `items.data` does not exist, can you post some more code? console.log() your response, what is it's exact shape? — Robbie Milejczak, Aug 15 '18 at 18:37
Can you provide a code example and the structure of the response you are receiving? — Hayden Carlson, Aug 15 '18 at 18:37

score 0 · Answer 1 · answered Aug 15 '18 at 18:44

I don't think there is enough context here to answer your question. Can you provide an example? In the meantime, I'll still try to help you.

I am not sure if your request is synchronous or asynchronous. Looking at your error, you are probably making an asynchronous request. When the first render() is called, items hasn't resolved yet. Therefore, item.data is undefined, which is the cause of your error.

A solution is to initialize the data property of this.state.item to an empty array [], that way your not calling the index operator of an undefined object.

Error in displaying JSON in react

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