Angular5到Angular6:Property 'map' does not exist on type 'Observable'.
错误原因:angular6不再支持原来的Http,用HttpClient代替了原来的Http解决方案:1.importimport{Http,Headers,Response}from'@angular/http'; 改为=>import{HttpClient,HttpHeaders,HttpParams}from'@angular/common/http';2.constructorconstr