嗨，我是新的Angular ，我一直在寻找一种方法来取代一个字符串，来自数据源的另一个显示在表行，例如：

if (element.transaction == "R"){ element.transaction = "Received"} else{ element.transaction = "Paid"}

我真的做了搜索，也许我的标准是错误的，但请不要给予我一个拇指下来没有搜索。
超文本标记语言

<!-- transactions Column -->
    <ng-container matColumnDef="transactions">
      <th mat-header-cell *matHeaderCellDef mat-sort-header>Transactions </th>
      <td mat-cell *matCellDef="let element">
        {{ element.transactions }}
      </td>
    </ng-container>

component.TS

export class ManualMovementsComponent implements OnInit, AfterViewInit {
  title = 'movement';

  movements: ManualMovements[] = [];

  movement: ManualMovements= {
    id: '',
    activ: true,
    name: '',
    code: '',
    transactions: '',
  };

displayedColumns: string[] = [
    'select',
    'name',
    'code',
    'transactions',
    'star',
  ];

 ngAfterViewInit() {
    this.dataSource = new MatTableDataSource<ManualMovements>(
      this.movements
    );```