value to outside of the api function to send the value via http and store it to the backend
import { Component, OnInit, ViewChild, ElementRef } from '@angular/core';
import { loadModules } from 'esri-loader';
@Component({
 selector: 'app-esri-map',
 templateUrl: './esri-map.component.html',
 styleUrls: ['./esri-map.component.css']
})
export class EsriMapComponent implements OnInit {
 public drawPointTest;
 public name = 'hello';
 public testdrawPointTest;
 // this is needed to be able to create the MapView at the DOM element in this component
 @ViewChild('mapViewNode') private mapViewEl: ElementRef;
 constructor() { }
 ngOnInit() {
 loadModules([
 'esri/Map',
 'esri/views/MapView',
 "esri/widgets/Sketch/SketchViewModel",
 "esri/Graphic",
 "esri/layers/GraphicsLayer"
 ])
 .then(([EsriMap, EsriMapView, SketchViewModel, Graphic, GraphicsLayer]) => {
 let editGraphic;
 // GraphicsLayer to hold graphics created via sketch view model
 const tempGraphicsLayer = new GraphicsLayer();
 const map = new EsriMap({
 basemap: 'gray',
 layers: [tempGraphicsLayer]
 });
 const mapView = new EsriMapView({
 container: this.mapViewEl.nativeElement,
 center: [90.399452, 23.777176],
 zoom: 10,
 map: map
 });
 mapView.when(function () {
 // create a new sketch view model
 const sketchViewModel = new SketchViewModel({
 view: mapView,
 layer: tempGraphicsLayer,
 pointSymbol: {
 type: "simple-marker", // autocasts as new SimpleMarkerSymbol()
 style: "square",
 color: "#8A2BE2",
 size: "16px",
 outline: { // autocasts as new SimpleLineSymbol()
 color: [255, 255, 255],
 width: 3
 }
 },
 polylineSymbol: {
 type: "simple-line", // autocasts as new SimpleLineSymbol()
 color: "#8A2BE2",
 width: "4",
 style: "dash"
 },
 polygonSymbol: {
 type: "simple-fill", // autocasts as new SimpleFillSymbol()
 color: "rgba(138,43,226, 0.8)",
 style: "solid",
 outline: {
 color: "white",
 width: 1
 }
 }
 });
 setUpClickHandler();
 // Listen to create-complete event to add a newly created graphic to view
 sketchViewModel.on("create-complete", addGraphic);
 // Listen the sketchViewModel's update-complete and update-cancel events
 sketchViewModel.on("update-complete", updateGraphic);
 sketchViewModel.on("update-cancel", updateGraphic);
 //*************************************************************
 // called when sketchViewModel's create-complete event is fired.
 //*************************************************************
 function addGraphic(event) {
 // Create a new graphic and set its geometry to
 // `create-complete` event geometry.
 const graphic = new Graphic({
 geometry: event.geometry,
 symbol: sketchViewModel.graphic.symbol
 });
 alert(JSON.stringify(event.geometry));
 this.drawPointTest = event.geometry;
 console.log(this.drawPointTest);
 console.log(this.drawPointTest.spatialReference.latestWkid);
 this.testdrawPointTest = this.drawPointTest.spatialReference.latestWkid;
 // this.sendDrawPont(event.geometry);
 this.sendDrawPont();
 tempGraphicsLayer.add(graphic);
 }
 //***************************************************************
 // called when sketchViewModel's update-complete or update-cancel
 // events are fired.
 //*************************************************************
 function updateGraphic(event) {
 // event.graphic is the graphic that user clicked on and its geometry
 // has not been changed. Update its geometry and add it to the layer
 event.graphic.geometry = event.geometry;
 tempGraphicsLayer.add(event.graphic);
 // set the editGraphic to null update is complete or cancelled.
 editGraphic = null;
 }
 // ************************************************************************************
 // set up logic to handle geometry update and reflect the update on "tempGraphicsLayer"
 // ************************************************************************************
 function setUpClickHandler() {
 mapView.on("click", function (event) {
 mapView.hitTest(event).then(function (response) {
 var results = response.results;
 // Found a valid graphic
 if (results.length && results[results.length - 1]
 .graphic) {
 // Check if we're already editing a graphic
 if (!editGraphic) {
 // Save a reference to the graphic we intend to update
 editGraphic = results[results.length - 1].graphic;
 // Remove the graphic from the GraphicsLayer
 // Sketch will handle displaying the graphic while being updated
 tempGraphicsLayer.remove(editGraphic);
 sketchViewModel.update(editGraphic);
 }
 }
 });
 });
 }
 //*************************************
 // activate the sketch to create a point
 //*************************************
 var drawPointButton = document.getElementById("pointButton");
 drawPointButton.onclick = function () {
 // set the sketch to create a point geometry
 sketchViewModel.create("point");
 setActiveButton(this);
 };
 //****************************************
 // activate the sketch to create a polyline
 //****************************************
 var drawLineButton = document.getElementById("polylineButton");
 drawLineButton.onclick = function () {
 // set the sketch to create a polyline geometry
 sketchViewModel.create("polyline");
 setActiveButton(this);
 };
 //***************************************
 // activate the sketch to create a polygon
 //***************************************
 var drawPolygonButton = document.getElementById("polygonButton");
 drawPolygonButton.onclick = function () {
 // set the sketch to create a polygon geometry
 sketchViewModel.create("polygon");
 setActiveButton(this);
 };
 //***************************************
 // activate the sketch to create a rectangle
 //***************************************
 var drawRectangleButton = document.getElementById(
 "rectangleButton");
 drawRectangleButton.onclick = function () {
 // set the sketch to create a polygon geometry
 sketchViewModel.create("rectangle");
 setActiveButton(this);
 };
 //***************************************
 // activate the sketch to create a circle
 //***************************************
 var drawCircleButton = document.getElementById("circleButton");
 drawCircleButton.onclick = function () {
 // set the sketch to create a polygon geometry
 sketchViewModel.create("circle");
 setActiveButton(this);
 };
 //**************
 // reset button
 //**************
 document.getElementById("resetBtn").onclick = function () {
 sketchViewModel.reset();
 tempGraphicsLayer.removeAll();
 setActiveButton(this);
 };
 function setActiveButton(selectedButton) {
 // focus the view to activate keyboard shortcuts for sketching
 mapView.focus();
 var elements = document.getElementsByClassName("active");
 for (var i = 0; i < elements.length; i++) {
 elements[i].classList.remove("active");
 }
 if (selectedButton) {
 selectedButton.classList.add("active");
 }
 }
 });
 })
 .catch(err => {
 console.error(err);
 });
 }
 sendDrawPont() {
 alert(this.testdrawPointTest);
 }
}