通常是因为Mat Autocomplete没有正确连接到FormControl。可以尝试在FormControl和Mat Autocomplete之间添加[(ngModel)]，或者使用[formControl]属性替换[matAutocomplete]属性。

示例代码如下：

HTML模板：

{{ option }}

组件：

import { Component, OnInit } from '@angular/core'; import { FormControl } from '@angular/forms'; import { Observable } from 'rxjs'; import { map, startWith } from 'rxjs/operators';

@Component({ selector: 'app-autocomplete', templateUrl: './autocomplete.component.html', styleUrls: ['./autocomplete.component.css'] }) export class AutocompleteComponent implements OnInit { myControl = new FormControl(); options: string[] = ['Option 1', 'Option 2', 'Option 3']; filteredOptions: Observable;

constructor() { }

ngOnInit() { this.filteredOptions = this.myControl.valueChanges .pipe( startWith(''), map(value => this._filter(value)) ); }

private _filter(value: string): string[] { const filterValue = value.toLowerCase();

return this.options.filter(option => option.toLowerCase().includes(filterValue));

} }