Angular MatPaginator 和 Azure Table 存储

Question

我正在尝试实现一个带有分页功能的 Angular material table，它连接到后端，从 Azure Table 存储中检索数据。

我知道，Table 存储支持 ExecuteQuerySegmentedAsync, which returns TableContinuationToken。看起来不错。所以在前端，我得到这样的东西：

interface IPagedResult<T> {
    items: T[];
    isFinalPage: boolean;
    continuationToken: string;
}

interface ILog {
    enqueuedDate: string;
    ...
}

component.ts 中的某处：


private logsTableSource: MatTableDataSource<ILog>;
@ViewChild(MatPaginator)paginator: MatPaginator;

ngAfterViewInit() {
   myService.GetRecords(this.paginator.pageSize)
            .subscribe(
               (res: IPagedResult<ILog>) => {
                    this.logsTableSource = new MatTableDataSource<ILog>(res.items);
               });
}

现在我想知道，如何获取页数？并让服务器知道我想要什么特定页面？

continuationToken 看起来像这样：

事实上，我可以用这个 continuationToken 做什么？

为了更好地理解 table 的样子：

Answer 1

您链接到的 TableContinuationToken 文档还指出：

A method that may return a partial set of results via a TableResultSegment object also returns a continuation token, which can be used in a subsequent call to return the next set of available results.

这意味着令牌可用于获取下一组可用结果，您不能将它们用作分页索引。无法为结果的第 7 页制作 TableContinuationToken。

Answer 2

正如@rickvdbosch 所说，TableContinuationToken 只希望继续前进。在对分页器进行一些更改后，我只能向前和向后移动。看起来不错，适合我：

如果有人感兴趣。以下是更改：

实施您自己的 MatPaginatorIntl 以删除页面标签。我的样子是这样的：

@Injectable()
export class LogsPaginator extends MatPaginatorIntl {
    public getRangeLabel = function (page: number, pageSize: number, length: number) {
        return '';
    };
}

您之前加载的缓存项目，因为我们可以 ONLY 使用 TableContinuationToken 向前移动。您的 component.ts 应如下所示：

export class LogsComponent {
  // As table storage does not support paging per index, we should cache already loaded logs and use continuation token if needed.

  private cachedLogs: ILog[] = [];
  private cachedIndexes: number[] = [];
  private continuationToken = '';

  ngOnInit() {
    this.paginator.page.subscribe(this.pageChanged.bind(this));
  }

  async ngAfterViewInit() {
    await this.loadLogs();
  }

  private async pageChanged(event: PageEvent) {
    if (event.previousPageIndex < event.pageIndex && this.cachedIndexes.indexOf(event.pageIndex) === -1) {
      await this.loadLogs();
    } else {
      this.redrawTable();
    }
  }

  private redrawTable() {
    const start = this.paginator.pageIndex * this.paginator.pageSize;
    const end = start + this.paginator.pageSize;
    this.logsTableSource.data = this.cachedLogs.slice(start, end);
  }


  private async loadLogs() {
      const res = await this.myService.GetLogs(this.paginator.pageSize, this.continuationToken).toPromise();
      this.cachedIndexes.push(this.paginator.pageIndex);
      this.cachedLogs.push(...res.items);
      this.paginator.length = res.isFinalPage ? this.cachedLogs.length : this.cachedLogs.length + 1;
      this.continuationToken = res.continuationToken;

      this.redrawTable();
  }
}

Angular MatPaginator 和 Azure Table 存储

Angular MatPaginator and Azure Table Storage

angular

angular-material

azure-table-storage

azure-tablequery

mat-pagination