在使用mat-sort进行表格排序时，需要在要排序的列上添加mat-sort-header属性，并将所需的排序依据指定为mat-sort-header的值。 在ng-modal中使用mat-sort时，需要在ng-modal所在组件中导入MatTableModule和MatSortModule模块，并在ngOnInit函数中初始化MatSort实例，并将其赋值给matSort属性。然后，在模板文件中，将matSort属性绑定到mat-table的matSort属性上，以激活mat-sort。 以下是一个示例代码： component.ts:

import { Component, OnInit, ViewChild } from '@angular/core';
import { MatSort } from '@angular/material/sort';
import { MatTableDataSource } from '@angular/material/table';

@Component({
  selector: 'app-table',
  templateUrl: './table.component.html',
  styleUrls: ['./table.component.css']
})
export class TableComponent implements OnInit {
  @ViewChild(MatSort) sort: MatSort;

  displayedColumns: string[] = ['position', 'name', 'weight', 'symbol'];
  dataSource = new MatTableDataSource(ELEMENT_DATA);

  ngOnInit() {
    this.dataSource.sort = this.sort;
  }
}

export interface Element {
  name: string;
  position: number;
  weight: number;
  symbol: string;
}

const ELEMENT_DATA: Element[] = [
  {position: 1, name: 'Hydrogen', weight: 1.0079, symbol: 'H'},
  {position: 2, name: 'Helium', weight: 4.0026, symbol: 'He'},
  {position: 3, name: 'Lithium', weight: 6.941, symbol: 'Li'},
  {position: 4, name: 'Beryllium', weight: 9.0122, symbol: 'Be'},
  {position: 5, name: 'Boron', weight: 10.81, symbol: 'B'},
  {position: 6, name: 'Carbon', weight: 12.011, symbol: 'C'},
  {position: 7, name: 'Nitrogen', weight: 14.007, symbol