在我的config.cs中。这已经启用了cors。 Nus软件包中已经安装了cors:
public static void Register(HttpConfiguration config)
{
// Web API configuration and services
SystemDiagnosticsTraceWriter traceWriter = config.EnableSystemDiagnosticsTracing();
traceWriter.IsVerbose = true;
traceWriter.MinimumLevel = TraceLevel.Debug;
// Enable Web API routes by attribute
config.MapHttpAttributeRoutes();
EnableCorsAttribute cors = new EnableCorsAttribute("*","*","*");
config.EnableCors(cors);
}