Выполнить npm i xlsx
HTML:
<div class="example-container mat-elevation-z8 " #TABLE>
<table mat-table #table [dataSource]="dataSource">
<!--- Note that these columns can be defined in any order.
The actual rendered columns are set as a property on the row definition" -->
<!-- Position Column -->
<ng-container matColumnDef="position">
<th mat-header-cell *matHeaderCellDef> No. </th>
<td mat-cell *matCellDef="let element"> {{element.position}} </td>
//..................................rest of the html
<button mat-raised-button color="primary" (click)="exportAsExcel()">Export as Excel</button></div>
В вашем компоненте
import {Component,ViewChild, ElementRef} from '@angular/core';
import * as XLSX from 'xlsx';
//......
export class AppComponent {
@ViewChild('TABLE') table: ElementRef;
exportAsExcel()
{
const ws: XLSX.WorkSheet=XLSX.utils.table_to_sheet(this.table.nativeElement);//converts a DOM TABLE element to a worksheet
const wb: XLSX.WorkBook = XLSX.utils.book_new();
XLSX.utils.book_append_sheet(wb, ws, 'Sheet1');
/* save to file */
XLSX.writeFile(wb, 'SheetJS.xlsx');
}
}
Демо : https://stackblitz.com/edit/angular-uyanwz