NG-bootstrap 和 Angular 9 兼容性

升级到 Angular 9 后，我收到以下与 ng-bootstrap 相关的错误：

src/app/shared/Components/form-controls/dropdown-select/dropdown-select.component.ts 中出现错误：87:63 - 错误 TS2304：找不到名称“NgbDropdownMenu”。

87 @ViewChild('dropdownMenu', { static: false }) dropDownMenu: NgbDropdownMenu; ~~~~~~~~~~~~~~~ src/app/private/private-shared/Services/ngb-modal-stack-extend.service.ts:1:39 - 错误 TS2305：模块 '"../../../../../。 ./../../../../../node_modules/@ng-bootstrap/ng-bootstrap"' 没有导出成员“isString”。 1 导入 { NgbModalRef、NgbActiveModal、isString、isDefined、NgbModalBackdrop、ContentRef、NgbModal、 NgbModalWindow } 来自 '@ng-bootstrap/ng-bootstrap'; ~~~~~~~~~ src/app/private/private-shared/Services/ngb-modal-stack-extend.service.ts:1:49 - 错误 TS2305：模块 '“../../../../../../../../../../../node_modules/@ng-bootstrap/ng-bootstrap/ng-bootstrap” ' 没有 导出成员“isDefined”。 1 导入 { NgbModalRef、NgbActiveModal、isString、isDefined、NgbModalBackdrop、ContentRef、NgbModal、 NgbModalWindow } 来自 '@ng-bootstrap/ng-bootstrap'; ~~~~~~~~~ src/app/private/private-shared/Services/ngb-modal-stack-extend.service.ts:1:60 - 错误 TS2305：模块 '"../../../../../。 ./../../../../../node_modules/@ng-bootstrap/ng-bootstrap/ng-bootstrap"' 没有 导出成员“NgbModalBackdrop”。

1 导入 { NgbModalRef、NgbActiveModal、isString、isDefined、NgbModalBackdrop、ContentRef、NgbModal、 NgbModalWindow } 来自 '@ng-bootstrap/ng-bootstrap'; ~~~~~~~~~~~~~~~~ src/app/private/private-shared/Services/ngb-modal-stack-extend.service.ts:1:78 - 错误 TS2305：模块 '“../../../../../../../../../../../node_modules/@ng-bootstrap/ng-bootstrap/ng-bootstrap” ' 没有 导出成员“ContentRef”。 1 导入 { NgbModalRef、NgbActiveModal、isString、isDefined、NgbModalBackdrop、ContentRef、NgbModal、 NgbModalWindow } 来自 '@ng-bootstrap/ng-bootstrap'; ～～～～～～～ src/app/private/private-shared/Services/ngb-modal-stack-extend.service.ts:1:100 - 错误 TS2305： 模块'“../../../../../../../../../../../node_modules/@ng-bootstrap/ng-bootstrap/ng-bootstrap “' 有 没有导出成员“NgbModalWindow”。

1 导入 { NgbModalRef、NgbActiveModal、isString、isDefined、NgbModalBackdrop、ContentRef、NgbModal、 NgbModalWindow } 来自 '@ng-bootstrap/ng-bootstrap';

Package.json 

    "@angular/cdk": "9.2.4",
    "@angular/common": "9.1.11",
    "@angular/compiler": "9.1.11",
    "@angular/core": "9.1.11",
    "@angular/forms": "9.1.11",
    "@angular/localize": "9.1.11",
    "@angular/material": "9.2.4",
    "@angular/platform-browser": "9.1.11",
    "@angular/platform-browser-dynamic": "9.1.11",
    "@angular/router": "9.1.11",
    "@ng-bootstrap/ng-bootstrap": "4.1.2",
    "rxjs": "6.3.3",
    },
    "devDependencies": {
       "@angular-builders/jest": "^7.2.0",
      "@angular-devkit/build-angular": "~0.1000.0",
      "@angular/cli": "^9.1.9",
      "@angular/compiler-cli": "9.1.11",
      "@schematics/angular": "^9.1.5",
  

更新与下表相关的版本

  ng-bootstrap    Angular Bootstrap CSS
    1.x.x           5.0.2   4.0.0
    2.x.x           6.0.0   4.0.0
    3.x.x           6.1.0   4.0.0
    4.x.x           7.0.0   4.0.0
    5.x.x           8.0.0   4.3.1
    6.x.x           9.0.0   4.4.1
    7.x.x          10.0.0   4.5.0