Client-side People Picker control for Sharepoint

$(document).ready(function () {

    SP.SOD.executeFunc('sp.js', 'SP.ClientContext', sharePointReady);

})

function sharePointReady() {

    context = new SP.ClientContext.get_current();

    web = context.get_web();

    getUser().done(function (user) {

        var schema = {};

        schema['PrincipalAccountType'] = 'User,DL,SecGroup,SPGroup';

        schema['SearchPrincipalSource'] = 15;

        schema['ResolvePrincipalSource'] = 15;

        schema['AllowMultipleValues'] = false;

        schema['MaximumEntitySuggestions'] = 50;

        schema['Width'] = '280px';

        var users = new Array(1);

        var defaultUser = new Object();

        defaultUser.AutoFillDisplayText = user.get_title();

        defaultUser.AutoFillKey = user.get_loginName();

        defaultUser.Description = user.get_email();

        defaultUser.DisplayText = user.get_title();

        defaultUser.EntityType = "User";

        defaultUser.IsResolved = true;

        defaultUser.Key = user.get_loginName();

        defaultUser.Resolved = true;

        users[0] = defaultUser;

        SPClientPeoplePicker_InitStandaloneControlWrapper('peoplePickerDiv', users, schema);

    });

}

function getUser() {

    var dfd = $.Deferred(function () {

        user = web.get_currentUser();

        context.load(user);

        context.executeQueryAsync(

            function () {

                dfd.resolve(user);

            }),

            function () {

                dfd.reject(args.get_message());

            };

    });

    return dfd.promise();

}

JSLink Urls

JSLink URLs and Tokens
When you are constructing your JSLink URL there are a number of tokens you can take advantage of:

• ~site – reference to the current SharePoint site (or “Web”)
• ~sitecollection – reference to the current SharePoint site collection (or “Site”)
• ~layouts – version specific reference to the web application Layouts folder (so it will automatically swap out /_layouts/14 or /_layouts/15 for you)
• ~sitecollectionlayouts – reference to the layouts folder in the current site collection (e.g. /sites/team/_layouts/15)
• ~sitelayouts – reference to the layouts folder in the current site (e.g. /sites/teams/subsite/_layouts/15)

Export to Excel using javascript

http://www.c-sharpcorner.com/UploadFile/65794e/export-from-html-table-using-jquery/

How to get spfielduser value in REST call ?

use below kind of query to get the SPFieldUserValue in REST based call

url: _spPageContextInfo.webAbsoluteUrl + "/_api/web/lists/getbytitle('" + listName + "')/Items?$select=Title,EmployeePhone,LeaveCategory,EmployeeLocation,EmployeeName/Title&$expand=EmployeeName&$filter="+ restQuery,

CRUD Operations using JSOM

Add :- 

function Add() {
    var clientContext = new SP.ClientContext();
    var oWeb = clientContext.get_web();
    var oList = oWeb.get_lists().getByTitle('List1');//Get SPList by Title
    var itemCreateInfo = new SP.ListItemCreationInformation();

    var oListItem = oList.addItem(itemCreateInfo);
    oListItem.set_item('Title', 'Value'); //Title is the field and Value is the value for field
    oListItem.update();

    clientContext.load(oListItem);
    clientContext.executeQueryAsync(Function.createDelegate(this, onQuerySucceeded), Function.createDelegate(this, onQueryFailed));

    //Function when the execution of the query successed
    function onQuerySucceeded(sender, args) {
        alert('Data ADDED successfully');
    };
    //Function to run when the execution falis
    function onQueryFailed(sender, args) {
        alert('Cannot ADD');
    };

};

Update :- 
function Update() {
    var clientContext = new SP.ClientContext();
    var oWeb = clientContext.get_web();
    var oList = oWeb.get_lists().getByTitle('List1');//Get SPList by Title

    var oListItem = oList.getItemById(1);//Get the list item by id
    oListItem.set_item('Title', 'New Value');
    oListItem.update();
    clientContext.executeQueryAsync(Function.createDelegate(this, onQuerySucceeded), Function.createDelegate(this, onQueryFailed));

    //Function when the execution of the query successed
    function onQuerySucceeded(sender, args) {
        alert('Data UPDATED successfully');
    };
    //Function to run when the execution falis
    function onQueryFailed(sender, args) {
        alert('Cannot UPDATE');
    };
};

Delete :-

function Delete() {
    var clientContext = new SP.ClientContext();
    var oWeb = clientContext.get_web();
    var oList = oWeb.get_lists().getByTitle('List1');//Get SPList by Title

    var oListItem = oList.getItemById(1);//Get the list item by id
   oListItem.deleteObject();
    clientContext.executeQueryAsync(Function.createDelegate(this, onQuerySucceeded), Function.createDelegate(this, onQueryFailed));

    //Function when the execution of the query successed
    function onQuerySucceeded(sender, args) {
        alert('Data DELETED successfully');
    };
    //Function to run when the execution falis
    function onQueryFailed(sender, args) {
        alert('Cannot DELETE');
    };
};