Indent JSON with JavaScript

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Working with XML and JavaScript is a nightmare, which is why JSON has become gold in the development community.  Hell, I even wrote a function to turn XML to JSON with JavaScript.  If you want to turn an existing object into well formatted JSON, you can you JSON.stringify(obj), but you already know that.  What you may not know is that you can do pretty formatting when generating JSON from objects!

The secret is using the third JSON.stringify argument which represents the space indentation levels:

var formatted = JSON.stringify(myObject, null, 2);

/*
	Result:

	{
		"myProp": "myValue",
		"subObj": {
			"prop": "value"
		}
	}

*/

The resulting JSON representation will be formatted and indented with two spaces!

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Discussion

  1. MaxArt

    For more advanced formatting, I’ve developed a tool for the intent:
    https://github.com/MaxArt2501/json-fmt
    It works a client library or a server module for node/io.js, has a CLI, and a Grunt and a Gulp plugin.

    Of course, if you need speed just use JSON.stringify.

    Sorry for the self-promotion.

  2. You can also format a JSON file in the terminal with a single command.

    python -m json.tool unformatted.json > formatted.json

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