1.在测试文件中引入ChangeDetectorRef：

import { Component, ChangeDetectorRef } from '@angular/core'; import { ComponentFixture, TestBed } from '@angular/core/testing';

2.对于每个测试用例，在BeforeEach块中创建一个新的实例，并使用changeDectectorRef的detectChanges方法手动调用变更检测：

describe('MyComponent', () => { let component: MyComponent; let fixture: ComponentFixture; let changeDetectorRef: ChangeDetectorRef;

beforeEach(async () => { await TestBed.configureTestingModule({ declarations: [ MyComponent ] }) .compileComponents(); });

beforeEach(() => { fixture = TestBed.createComponent(MyComponent); component = fixture.componentInstance; changeDetectorRef = fixture.debugElement.injector.get(ChangeDetectorRef); fixture.detectChanges(); });

it('should update input value', () => { component.myInputValue = 'new value'; changeDetectorRef.detectChanges(); expect(component.myInputValue).toEqual('new value'); }); });

3.确保对应的组件输入属性有输入绑定：

@Component({ template: }) export class MyComponent { @Input() myInputValue: string; }