<table mat-table [dataSource]="billingLines" class="mat-elevation-z8">

    <!-- Other columns comes here -->

    <ng-container matColumnDef="period">
        <th mat-header-cell *matHeaderCellDef> Période </th>
        <td mat-cell *matCellDef="let element; let i=index;">
            <p>{{element.getPeriodString()}}</p>
        </td>
    </ng-container>

    <tr mat-header-row *matHeaderRowDef="displayedColumns"></tr>
    <tr mat-row *matRowDef="let row; columns: displayedColumns;"></tr>
</table>

@Input() billingLines: ContractBillingLine[] = [];

export class ContractBillingLine {
    constructor(
        public ligneTitle: string,
        public creditNote: boolean,
        public startPeriod: Date,
        public endPeriod: Date,
        public sumHT: number,
        public sumTVA: number,) {
    }

    public getPeriodString(): string {
        return "Du " + moment(this.startPeriod).format("dd/mm/yyyy") + moment(this.endPeriod).format("dd/mm/yyyy");
    }
}