What is an easy way to get Google Spreadsheet content as JSON using Google Apps Script?

Question

What is an easy way to get the contents of a Google spreadsheet as JSON using Google Apps Script?

Answer 1

In a Google spreadsheet, go to Tools > Scripts > Script Editor

Paste this code and click play

function getValues() {
  var range = SpreadsheetApp.getActiveSheet().getDataRange();
  var json = Utilities.jsonStringify(range.getValues())
  Browser.msgBox(json);
}​