Identify QuickLaunch is Enabled for SharePoint Site Using REST API

This blog contains the REST API syntax and code used to check whether the QuickLaunch is visible or hidden on the SharePoint site.

Syntax

REST API Endpoint:

https://SharePointSiteURL/_api/web?$select=QuickLaunchEnabled

REST API endpoint to use in Add_ins:

<appweburl>/_api/SP.AppContextSite(@target)/web?$select=QuickLaunchEnabled&@target=<hostweburl>

Embed Code Snippet

The following code snippet can be embed in SharePoint page or in content editor web part as a script. This example used to check whether the quick launch is enabled for the SharePoint website. 

<script type="text/javascript" src="/SiteAssets/Scripts/jquery.min.js"></script>
<script type="text/javascript">
    $.ajax(
    {
        url: _spPageContextInfo.webAbsoluteUrl + "/_api/web?$select=quicklaunchenabled", //THE ENDPOINT
        method: "GET",
        headers:
        {
            "Accept": "application/json; odata=verbose"
        },
        success: function(data)
        {
            //RESULTS HERE!!
            console.log(data.d.QuickLaunchEnabled)
            if (data.d.QuickLaunchEnabled)
                alert('Quick launch enabled on this site.');
            else
                alert('Quick launch disabled on this site.');
        }
    });
</script>

Add-in Code Snippet

The following code snippet is used in SharePoint Add-in to get the boolean property of QuickLaunchEnabled for the SharePoint website. 

// Load the js files and continue to the successHandler
$.getScript(scriptbase + "SP.RequestExecutor.js", execCrossDomainRequest);

// Function to prepare and issue the request to get
// SharePoint data
function execCrossDomainRequest()
{
    // Initialize the RequestExecutor with the add-in web URL.
    var executor = new SP.RequestExecutor(appweburl);
    // Issue the call against the add-in web.
    // To get the QuickLaunchEnabled property using REST we can hit the endpoint:
    // appweburl/_api/web?select=QuickLaunchEnabled&@target=hostweburl
    // The response formats the data in the JSON format.
    executor.executeAsync(
    {
        url: appweburl + "/_api/SP.AppContextSite(@target)/web?$select=quicklaunchenabled&@target='" + hostweburl + "'",
        method: "GET",
        headers:
        {
            "Accept": "application/json; odata=verbose"
        },
        success: successHandler,
        error: errorHandler
    });
}
// Function to handle the success event.
function successHandler(data)
{
    var jsonObject = JSON.parse(data.body)
        //jsonObject.d.QuickLaunchEnabled returns true if enabled otherwise it returns false
    console.log('Tree view enabled on this site: ' + jsonObject.d.QuickLaunchEnabled);
    if (jsonObject.d.QuickLaunchEnabled)
        $('#message').html('Quick launch enabled on this site.');
    else
        $('#message').html('Quick launch disabled on this site.');
}

function errorHandler(data, errorCode, errorMessage)
{
    console.log("Could not complete cross-domain call: " + errorMessage);
}