BasicProperties class

var basicProperties = fileInformation.basicProperties;

var file = SdkSample.sampleFile;
if (file !== null) {
    var outputDiv = document.getElementById("output");

    // Get top level file properties
    outputDiv.innerHTML = "Filename: " + file.name + "<br />";
    outputDiv.innerHTML += "File type: " + file.fileType + "<br />";

    // Get basic properties
    file.getBasicPropertiesAsync().then(function (basicProperties) {
        outputDiv.innerHTML += "Size: " + basicProperties.size + " bytes<br />";
        outputDiv.innerHTML += "Date modified: " + basicProperties.dateModified + "<br />";

        // Get extra properties
        return file.properties.retrievePropertiesAsync([fileOwnerProperty, dateAccessedProperty]);
    }).done(function (extraProperties) {
        var propValue = extraProperties[dateAccessedProperty];
        if (propValue !== null) {
            outputDiv.innerHTML += "Date accessed: " + propValue + "<br />";
        }
        propValue = extraProperties[fileOwnerProperty];
        if (propValue !== null) {
            outputDiv.innerHTML += "File owner: " + propValue;
        }
    },
    // Handle errors with an error function
	function (error) {
	    // Handle errors encountered while retrieving properties
    });
}