HarmonyOS 路由参数如何接收？

import { router } from '@kit.ArkUI'  
@Entry  
@Component  
struct PageA {  
  build() {  
    Column() {  
      Button('跳转至PageB')  
        .onClick(() => {  
          router.pushUrl({  
            url: "pages/test/PageB"  
          })  
        })  
      Button('跳转至PageC')  
        .onClick(() => {  
          router.pushUrl({  
            url: "pages/test/PageC"  
          })  
        })  
    }.width('100%').height('100%').alignItems(HorizontalAlign.Center).justifyContent(FlexAlign.Center)  
  }  
  onPageShow(): void {  
    let params = router.getParams() as result;  
    if (params?.page == 'PageB') {  
      console.info('page B')  
    } else if (params?.page == 'PageC') {  
      console.info('page C')  
    }  
  }  
}  
class result {  
  page: string  
  result: PageResult  
  constructor(page: string, result: PageResult) {  
    this.page = page  
    this.result = result  
  }  
}  
export class PageResult{  
}