Question

我有一组选定的位置和all_locations。如果该位置出现在选定的位置，我想在mat-select选项中设置为selected。

Users_loc=[username:'A1',
    locations:{'A','B','C'}
]

all_loc=[location_name:'A',
        location_name:'B',
        location_name:'C',
        location_name:'D',
        location_name:'E',
        location_name:'F',...,
        location_name:'Y',
        location_name:'Z']

<div class="form-controls">
    <mat-form-field>
      <mat-select mulitple (selectionChange)="regionSelectionChange($event.value)" placeholder="Region">
        <mat-option *ngFor="let region of regions" [value]="region.location_name">{{region.location_name}}</mat-option>
      </mat-select>
    </mat-form-field>
</div>

我要在选型中选择A，B，C前面的复选标记。.

Answer 1

在选择时，如果您正在获取像这样的数据：[A，B，C]，则可以像这样通过[[ngModel）]传递这种类型的数组：

<mat-form-field>
      <mat-select (selectionChange)="regionSelectionChange($event.value)" placeholder="Region" multiple [(ngModel)]="selectedData">
        <mat-option *ngFor="let region of regions" [value]="region.location_name">{{region.location_name}}</mat-option>
      </mat-select>
</mat-form-field>

在TS中：

selectedData = [A,B,C]

如何在angular7的多个垫选择选项中设置选择的选项

1 个答案: