angular6页面刷新时报HTTP Status 404 – Not Found

错误信息：

HTTP Status 404 – Not Found
Type Status Report

Description The origin server did not find a current representation for the target resource or is not willing to disclose that one exists.

Apache Tomcat/8.5.40

解决方法----开启 Hash 模式

在app.module.ts中

1.导入 HashLocationStrategy 及 HashLocationStrategy

import { HashLocationStrategy,LocationStrategy } from "@angular/common";

2.配置 NgModule - providers

@NgModule({
  imports: [
    BrowserModule,
    RouterModule.forRoot(routes)
  ],
  ...,
  providers: [
    { provide: LocationStrategy, useClass: HashLocationStrategy }
  ]
})