Type ‘element[]’ is missing the following properties from type ‘reactelement‘: type, props, key

Explanation

The error message “type ‘element[]’ is missing the following properties from type ‘reactelement‘: type, props, key” occurs when we try to assign an array of elements to a variable or prop that is supposed to expect a single React element. The error indicates that the assigned value should be a React element with specified properties like ‘type’, ‘props’, and ‘key’.

To understand this better, let’s take an example. Suppose we have a parent component called ‘App’, and we want to pass an array of child elements to a prop called ‘children’ in the ‘App’ component.

    import React from 'react';

    const App = () => {
      const childElements = [
        <div>Child 1</div>,
        <div>Child 2</div>,
        <div>Child 3</div>
      ];

      return (
        <div>
          <ChildComponent children={childElements} />
        </div>
      );
    };

    const ChildComponent = ({ children }) => {
      return (
        <div>
          {children}
        </div>
      );
    };

    export default App;
  

In the above example, we have an array of child elements assigned to the ‘childElements’ variable. We pass this array as the ‘children’ prop to the ‘ChildComponent’.

However, this will result in the mentioned error because the ‘children’ prop in the ‘ChildComponent’ expects a single React element, not an array of elements.

To fix the error, we need to make sure that we pass a single React element as the value of the ‘children’ prop, rather than an array of elements. One way to achieve this is by using the ‘map’ function to iterate over the array and render each child element individually.

    const App = () => {
      const childElements = [
        <div key="1">Child 1</div>,
        <div key="2">Child 2</div>,
        <div key="3">Child 3</div>
      ];

      return (
        <div>
          {childElements.map(childElement => childElement)}
        </div>
      );
    };
  

In the updated example, we assigned a unique ‘key’ prop to each child element to satisfy the requirement of the ‘key’ property for a list of elements. We then used the ‘map’ function to iterate over the ‘childElements’ array and render each child element individually.

By ensuring that we pass individual elements rather than an array, the error has been resolved.