如何设置垫自动完成的默认值

本文介绍了如何设置垫自动完成的默认值的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！

问题描述

我在页面上有多个自动完成功能，并且能够选择值并保存它们.我需要的是下次加载该页面时，默认情况下应为已选择并保存的值显示预先选择的值.

I have multiple auto complete on a page and able to select values and save them. What I need is when I load the page next time, the pre selected values should be displayed by default for the ones already selected and saved.

以下是代码段-

<ng-container matColumnDef="course">
      <th mat-header-cell *matHeaderCellDef mat-sort-header> Course Section </th>
      <td mat-cell *matCellDef="let course"> {{course.courseSection}}
      <mat-form-field>
          <input type="text" id="{{course.courseSection}}" placeholder="Pick one" aria-label="Number" matInput [formControl]="myControl"
            [matAutocomplete]="auto">
          <mat-autocomplete #auto="matAutocomplete" (optionSelected)="onSelectionChanged(course.courseSection, $event)">
            <mat-option *ngFor="let option of filteredOptions | async" [value]="option">
              {{option}}
            </mat-option>
          </mat-autocomplete>
        </mat-form-field>
      </td>
    </ng-container>

在ngOnInit上，我能够获取保存在地图中的值，并且正在使用以下无效的逻辑-

On ngOnInit, I am able to get the values saved in a map and was using the below logic which doesn't work -

checkAssigned(section: string) {
    if (this.assigned.has(section)) {
      return this.assigned.get(section);
    } else {
      return '';
    }
}

HTML-

<mat-option *ngFor="let option of filteredOptions | async"
[value]="checkAssigned(course.courseSection)===''? option : checkAssigned(course.courseSection)">

但是它不起作用.有什么建议可以实现吗?

But it doesn't work. Any suggestions as how can I achieve it?

推荐答案

对于设置值，它应类似于您在matAutoComplete列表中使用的格式.

For setting values, it should similar to the format that you're using in the matAutoComplete list.

假设您正在使用类似 myNameList = [{{name:"My Name"，id:1}，{name:"My name 2"，id:2}]

然后，您需要设置值

this.myformName.controls['myControl'].setValue({name: "My Name", id:1}); //Working Code

如果设置类似，它将设置默认值

it will set the default value if you are setting like

this.myformName.controls['myControl'].setValue("My Name"); //Not working code

然后它将不起作用.

请检查此内容以供参考 https://stackblitz.com/edit/angular-8r153h-kpwhaa?file=app/autocomplete-display-example.ts

Please check this for reference https://stackblitz.com/edit/angular-8r153h-kpwhaa?file=app/autocomplete-display-example.ts

这篇关于如何设置垫自动完成的默认值的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！

EDIT