mat-table中的自定义过滤器

我正在使用mat-table . 它有一个过滤器,可以正常使用doc示例:

https://material.angular.io/components/table/overview起,原始代码为:

<div class="example-header">
       <mat-form-field>
         <input matInput (keyup)="applyFilter($event.target.value)" placeholder="Filter">
       </mat-form-field>
   </div>

   <mat-table #table [dataSource]="dataSource">
      <!-- the rest of the code -->
   </mat-table>
export class TableFilteringExample {
     displayedColumns = ['position', 'name', 'weight', 'symbol'];
     dataSource = new MatTableDataSource(ELEMENT_DATA);

     applyFilter(filterValue: string) {
       filterValue = filterValue.trim(); // Remove whitespace
       filterValue = filterValue.toLowerCase(); // MatTableDataSource defaults to lowercase matches
       this.dataSource.filter = filterValue;
     }
    }
    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: 10.811, symbol: 'B'}
    ];

通过此实现,当过滤时,它会过滤任何列 .

现在我正在尝试更改过滤器,因为我想要的是“name”列的过滤器,所以我试图重写过滤器并分配给filterData .

applyFilter(filterValue: string) {
        filterValue = filterValue.trim(); // Remove whitespace
        filterValue = filterValue.toLowerCase(); // MatTableDataSource defaults to lowercase matches
       this.dataSource.filteredData = this.filterByEmail(filterValue); 
        console.log(this.dataSource.filteredData); //value is what I want.
    }

    filterByName(filter: string): any {
      const dataFiltered = this.data.filter(function(item){
         return item.name.indexOf(filter) > -1
       })
        return dataFiltered;
    }

在控制台中,我可以看到this.dataSource.filteredData具有我想要打印的数据,但表没有重新加载 .

我错过了什么?

回答(2)

3 years ago

我找到了解决方案here .

有必要重写 filterPredicate ,并像往常一样使用它, filterPredicate 需要在过滤器通过时返回 true ,而 false 则不需要

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


dataSource = new MatTableDataSource(ELEMENT_DATA);
/* configure filter */
this.dataSource.filterPredicate = 
  (data: Element, filter: string) => data.name.indexOf(filter) != -1;


applyFilter(filterValue: string) {
   filterValue = filterValue.trim(); // Remove whitespace
   filterValue = filterValue.toLowerCase(); // MatTableDataSource defaults to lowercase matches
   this.dataSource.filter = filterValue;
 }

3 years ago

不要忘记在数据上应用 .trim().toLowerCase() ,否则可能会遇到意外结果 . 请参阅下面的示例:

this.dataSource.filterPredicate = (data:
  {name: string}, filterValue: string) =>
  data.name.trim().toLowerCase().indexOf(filterValue) !== -1;

applyFilter(filterValue: string) {
    this.dataSource.filter = filterValue.trim().toLowerCase();
}