发生这种情况的原因之一是在您的应用模块中，您有一个条目组件，构建过程无法找到其导入(在下面的示例中)如果我注释掉导入行并离开组件，则将导致此错误.).

One of the reasons this can happen is in you app module, you have an entry components which the build process can't find a import for (in below example if I comment out the import line and leave the component then it causes this error).