[javascript] How to loop and render elements in React.js without an array of objects to map?

Updated: As of React > 0.16

Render method does not necessarily have to return a single element. An array can also be returned.

var indents = [];
for (var i = 0; i < this.props.level; i++) {
  indents.push(<span className='indent' key={i}></span>);
}
return indents;

OR

return this.props.level.map((item, index) => (
    <span className="indent" key={index}>
        {index}
    </span>
));

Docs here explaining about JSX children


OLD:

You can use one loop instead

var indents = [];
for (var i = 0; i < this.props.level; i++) {
  indents.push(<span className='indent' key={i}></span>);
}
return (
   <div>
    {indents}
    "Some text value"
   </div>
);

You can also use .map and fancy es6

return (
   <div>
    {this.props.level.map((item, index) => (
       <span className='indent' key={index} />
    ))}
    "Some text value"
   </div>
);

Also, you have to wrap the return value in a container. I used div in the above example

As the docs say here

Currently, in a component's render, you can only return one node; if you have, say, a list of divs to return, you must wrap your components within a div, span or any other component.

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