JavaScript Interview Questions And Answers

1. IMMEDIATELY INVOKED FUNCTION EXPRESSION [IIFE]

Ans. http://prasadhonrao.com/javascript-functions-part-4-immediately-invoked-function-expression-iife/

       http://adripofjavascript.com/blog/drips/an-introduction-to-iffes-immediately-invoked-function-expressions.html

2. Javascript Closures

Ans. https://developer.mozilla.org/en/docs/Web/JavaScript/Closures

3. Javascript Constructors and Prototypes and Inheritance

Ans. http://tobyho.com/2010/11/22/javascript-constructors-and/

        http://phrogz.net/js/classes/OOPinJS2.html

        http://tobyho.com/2011/11/11/js-object-inheritance/

4. Variable and Function Hoisting in JavaScript

Ans. http://adripofjavascript.com/blog/drips/variable-and-function-hoisting

5.  Javascript Interview Question

Ans. http://stackoverflow.com/questions/11246/best-resources-to-learn-javascript

6. Object Oriented JavaScript Interview Questions and Answers

Ans. http://www.code-sample.com/2015/04/javascript-interview-questions-answers.html

7. Jquery Interview Question and answers

Ans. http://www.code-sample.com/2015/04/jquery-interview-questions-and-answers.html

8. Advance Javascript Interview Question

Ans. https://www.doppnet.com/10-advanced-javascript-interview-questions.html

9. 15 Minutes for JavaScript and AngularJS

Ans.      http://www.guru99.com/angularjs-tutorial.html?utm_source=careerguru99pdf&utm_medium=referral&utm_campaign=click

             http://www.guru99.com/interactive-javascript-tutorials.html

 

<!doctype html>
<html lang="en" ng-app="summit" class="summit-app">
<head>
  <style>
    img {
      opacity: 1;
      transition: opacity 0.3s;
    }

      img[data-src] {
        opacity: 0;
      }
  </style>
</head>
<body>
  <p>This is first Image</p>
  <img src="Chrysanthemum.jpg" />

  <p>This is 2nd Image</p>
  
    <img  data-echo="Desert.jpg" />
  

    <p>This is 3rd Image</p>
  
    <img  data-echo="Hydrangeas.jpg" />
  

    <p>This is 4th Image</p>
  
    <img  data-echo="Jellyfish.jpg" />
  

    <p>This is 5th Image</p>
  
    <img  data-echo="Koala.jpg" />
    

    <script>
      (function(){
        window.echo = (function (window, document) {

          'use strict';

          /*
           * Constructor function
           */
          var Echo = function (elem) {
            this.elem = elem;
            this.render();
            this.listen();
          };

          /*
           * Images for echoing
           */
          var echoStore = [];

          /*
           * Element in viewport logic
           */
          var scrolledIntoView = function (element) {
            var coords = element.getBoundingClientRect();
            return ((coords.top >= 0 && coords.left >= 0 && coords.top) <= (window.innerHeight || document.documentElement.clientHeight));
          };

          /*
           * Changing src attr logic
           */
          var echoSrc = function (img, callback) {
            img.src = img.getAttribute('data-echo');
            if (callback) {
              callback();
            }
          };

          /*
           * Remove loaded item from array
           */
          var removeEcho = function (element, index) {
            if (echoStore.indexOf(element) !== -1) {
              echoStore.splice(index, 1);
            }
          };

          /*
           * Echo the images and callbacks
           */
          var echoImages = function () {
            for (var i = 0; i < echoStore.length; i++) {
              var self = echoStore[i];
              if (scrolledIntoView(self)) {
                echoSrc(self, removeEcho(self, i));
              }
            }
          };

          /*
           * Prototypal setup
           */
          Echo.prototype = {
            init: function () {
              echoStore.push(this.elem);
            },
            render: function () {
              if (document.addEventListener) {
                document.addEventListener('DOMContentLoaded', echoImages, false);
              } else {
                window.onload = echoImages;
              }
            },
            listen: function () {
              window.onscroll = echoImages;
            }
          };

          /*
           * Initiate the plugin
           */
          var lazyImgs = document.querySelectorAll('img[data-echo]');
          for (var i = 0; i < lazyImgs.length; i++) {
            new Echo(lazyImgs[i]).init();
          }

        })(window, document);
      })();
    </script>
</body>
</html>


summitApp.directive('portfolioExposureByRegionDrillDownChart', ['$timeout', '$filter', '$window', '$rootScope', 'MSG_TOPICS',
  function ($timeout, $filter, $window, $rootScope, MSG_TOPICS) {
    return {
      restrict: 'E',
      require: '^baseChart',
      templateUrl: 'components/dashboard/portfolioDashboard/charts/portfolioExposureByRegionChart/portfolioExposureByRegionDrillDownChartTemplate.html',
      scope: {
        strategyId: '@',
        strategyDesc: '=',
        benchmarkDesc: '=',
        geoHierarchyId: '@',
        includeHistory: '@'
      },
      link: function (scope, element, attr, baseChartCtrl) {
        angular.element($window).bind('resize', scope.resizeChart);
        scope.chartHight = 210;
        scope.chartId = 'portfolioExposureByRegionDrillDownChart';
        scope.drilldownDateCategories = [];
        scope.createChart = function () {
          var baseChartObject = baseChartCtrl.createBaseChartObject();

          baseChartObject.chart.height = 250;
          baseChartObject.chart.spacingTop = 50;
          baseChartObject.loading = {
            labelStyle: {
              top: '45%',
              left: '40%',
              //backgroundImage: 'url("/app/img/ajax-loader_L.gif")',
              display: 'block',
              width: '136px',
              height: '26px',
              backgroundColor: '#777',
              align: 'center',
              color: '#fff',
              fontWeight: 'bold',
              fontSize: '15px'
            },
            opacity: 0.6,
            //backgroundColor: 'red',
            //top: '2px',
            width: '667px',
            height: '397px'
          };
          baseChartObject.chart = {
            type: 'column',
            backgroundColor: '#1e1e1e',
            plotBackgroundColor: '#1e1e1e',
            events: {
              drilldown: function (e) {

                this.yAxis[0].update({
                  tickInterval: 10
                }, false, false);

                if (!e.seriesOptions) {
                  var chart = this;
                  chart.plotWidth = chart.chartWidth;
                  chart.plotHeight = chart.chartHeight;
                  chart.plotLeft = 0;
                  chart.plotTop = 0;
                  chart.showLoading('Loading...');

                  var selectedColumn = e.point.name;
                  var regionFilteredData = _.filter(scope.weightByRegionData, { 'region_name': selectedColumn });
                  regionFilteredData = _.sortBy(regionFilteredData, 'date_value');

                  var portfolioWeightDataPoints = [];
                  var benchmarkWeightsDataPoints = [];
                  var drilldownDateCategories = [];

                  for (var i = 0; i < regionFilteredData.length; i++) {
                    drilldownDateCategories.push(Date.parse(regionFilteredData[i].date_value).valueOf());
                    portfolioWeightDataPoints.push([Date.parse(regionFilteredData[i].date_value).valueOf(), regionFilteredData[i].portfolio_weight]);
                    benchmarkWeightsDataPoints.push([Date.parse(regionFilteredData[i].date_value).valueOf(), regionFilteredData[i].benchmark_weight]);
                  }

                  chart.drilldowns = {
                    series1: {
                      type: 'line',
                      name: scope.strategyDesc,
                      data: portfolioWeightDataPoints,
                      color: '#59fffb'
                    },
                    series2: {
                      type: 'line',
                      name: scope.benchmarkDesc,
                      data: benchmarkWeightsDataPoints,
                      color: '#FFAD79'
                    }
                  };
                 
                  var series = [chart.drilldowns.series1, chart.drilldowns.series2];

                  setTimeout(function () {
                    chart.addSingleSeriesAsDrilldown(e.point, series[0]);
                    chart.addSingleSeriesAsDrilldown(e.point, series[1]);
                    chart.setTitle({ text: e.point.name + ' Region Weight Over Time' });
                    chart.applyDrilldown();
                    chart.hideLoading();
                    //chart.addSeriesAsDrilldown(e.point, series);                    
                  }, 1000);
                }
              },
              drillup: function (e) {
                this.yAxis[0].update({
                  tickInterval: 20
                }, false, false);

                var chart = this;
                chart.showLoading('Loading.....');
                chart.setTitle({ text: 'Weights By Region' });
                chart.hideLoading();
              }
            }
          };
          baseChartObject.legend = {
            enabled: true,
            itemStyle: {
              color: '#fff',
              fontWeight: 'bold'
            },
            itemHoverStyle: {
              color: '#fff'
            },
            itemHiddenStyle: {
              color: '#444'
            },
            //  borderColor: '#fff',
            borderWidth: 1,
            backgroundColor: '#2C3135',
            borderRadius: 5,
          };
          baseChartObject.title = {
            text: "Weights By Region",
            style: {
              color: '#fff'
            }
          };
          baseChartObject.chart.width = getContainerWidth();
          baseChartObject.plotOptions = {
            column: {
              allowPointSelect: false,
              dataLabels: {
                enabled: true,
                inside: false,
                align: 'center',
                shadow: false,
                style: {
                  color: '#fff',
                  textOutline: false,
                  fontWeight: 'bold',
                  fontSize: '11px'
                },
                formatter: function () {
                  return '<span style="color: white">' + Math.round(this.y) + '</span>';
                }
              }
            }
          };
          baseChartObject.xAxis = {
            id: 'xAxisCategory',
            type: 'category',
            categories: [],
            tickmarkPlacement: 'between',
            crosshair: false,
            labels: {
              style: {
                fontSize: '10px',
                color: '#fff',
                textDecoration: 'none',
                textTransform: 'uppercase'
              },
              useHTML: true,
              formatter: function () {
                var regionName = this.value.length > 4 ? this.value.substring(0, 6) : this.value;
                return '<span title="' + this.value + '" style="color:#fff; text-decoration:none !important;">' + regionName; + '</span>';
              },
              textDecoration: 'none'
            }
          };
          baseChartObject.yAxis = {
            id: 'leftY',
            min: 0,
            tickInterval: 20,
            labels: {
              x: -5,
              y: 4,
              style: {
                color: '#A4B5FF'
              }
            },
            title: {
              text: '',
              style: {
                color: '#A4B5FF',
                fontSize: '10px'
              }
            },
            gridLineWidth: 1,
            opposite: false,
            reversed: false
          };
          baseChartObject.tooltip.pointFormatter = function () {
            return '<span style="color: ' + this.color + '">' + this.series.name + '</span>: <b>' + Highcharts.numberFormat(this.y, 0) + '</b><br/>';
          };
          scope.chart = Highcharts.stockChart(scope.chartId, baseChartObject);
          scope.chart.showLoading("Loading...");
        };

        function getContainerWidth() {
          return element[0].parentElement.clientWidth - 50;
        }

        scope.close = function () {
          scope.onClose();
        };

        scope.resizeChart = function () {
          if (scope.chart)
            scope.chart.setSize(getContainerWidth(), scope.chartHeight);
        };

        scope.$watch(function () {
          return element[0].parentElement.clientWidth;
        },
        function (newValue, oldValue) {
          if (newValue != oldValue && scope.chart) {
            scope.resizeChart();
          }
        });

        scope.$watch('isBind', function () {
          scope.chart.hideLoading();
        });

        $timeout(function () {
          scope.createChart();
          $timeout(scope.resizeChart, 1000);
        }, 0);
      },
      controller: function ($scope, PortfolioDashboardService, $q) {
        $scope.weightByRegionData = [];

        var data = {
          'strategy_Id': $scope.strategyId,
          'geo_hierarchy_id': $scope.geoHierarchyId,
          'includeHistory': 'true'
        };
        $scope.portfolioWeightDataPoints = [];
        $scope.benchmarkWeightsDataPoints = [];
        $scope.categories = [];
        $scope.isBind = false;

        if ($scope.portfolioWeightDataPoints.length > 0 || $scope.benchmarkWeightsDataPoints.length > 0) {
          bindSeries();
        } else {
          getPortfolioExposureByResionData();
        }

        function bindSeries() {
          $scope.$watch('strategyDesc', function (newValue, oldValue) {
            if (newValue != null) {
              $scope.chart.xAxis[0].categories = $scope.categories;
              $scope.chart.addSeries({
                id: 'portfolioWeightData',
                color: '#59fffb',
                //  xAxis: 'xAxisCategory',
                lineWidth: 1,
                name: $scope.strategyDesc,
                data: $scope.portfolioWeightDataPoints
              });
              $scope.chart.addSeries({
                id: 'benchmarkWeightsData',
                color: '#FFAD79',
                //    xAxis: 'xAxisCategory',
                lineWidth: 1,
                name: $scope.benchmarkDesc,
                data: $scope.benchmarkWeightsDataPoints
              });
              $scope.isBind = true;
            }
          });
        };

        function getPortfolioExposureByResionData() {
          PortfolioDashboardService.getPortfolioExposureByResion(data).then(function (response) {
            $scope.weightByRegionData = response.data;
            if (response.data.length > 0) {

              var tmp_dt = response.data[0].date_value;
              var firstRowArray = [];

              for (var i = 0; i < response.data.length; ++i) {
                if (response.data[i].date_value == tmp_dt) {
                  if (response.data[i].benchmark_weight > 1) {
                    firstRowArray.push(response.data[i]);
                  }
                }
                else
                  break;
              }

              if (firstRowArray.length > 0) {
                var categories = [];
                var portfolioWeightDataPoints = [];
                var benchmarkWeightsDataPoints = [];

                for (var i = 0; i < firstRowArray.length; i++) {
                  categories.push(firstRowArray[i].region_name);
                  portfolioWeightDataPoints.push({ name: firstRowArray[i].region_name, y: firstRowArray[i].portfolio_weight, drilldown: { region_name: firstRowArray[i].region_name } });
                  benchmarkWeightsDataPoints.push({ name: firstRowArray[i].region_name, y: firstRowArray[i].benchmark_weight, drilldown: { region_name: firstRowArray[i].region_name } });
                }
                $scope.categories = categories;
                $scope.portfolioWeightDataPoints = portfolioWeightDataPoints;
                $scope.benchmarkWeightsDataPoints = benchmarkWeightsDataPoints;
                bindSeries();
              }
            }
          });
        };
      }
    };
  }]);