我有这个控制器:
package web import ( "net/http" ) func init() { } func (controller *Controller) Index(r *http.Request) (string, int) { return "Testing", http.StatusOK }
使用此处理程序:
type Application struct { } func (application *Application) Route(controller interface{}, route string) http.HandlerFunc { return func(w http.ResponseWriter, r *http.Request) { var ptr reflect.Value var value reflect.Value var finalMethod reflect.Value value = reflect.ValueOf(controller) // if we start with a pointer, we need to get value pointed to // if we start with a value, we need to get a pointer to that value if value.Type().Kind() == reflect.Ptr { ptr = value value = ptr.Elem() } else { ptr = reflect.New(reflect.TypeOf(controller)) temp := ptr.Elem() temp.Set(value) } // check for method on value method := value.MethodByName(route) if method.IsValid() { finalMethod = method } // check for method on pointer method = ptr.MethodByName(route) if method.IsValid() { finalMethod = method } methodInterface := finalMethod.Call([]reflect.Value{})[0].Interface() method_route := methodInterface.(func(r *http.Request) (string, int)) body, code := method_route(r) switch code { case http.StatusOK: io.WriteString(w, body) case http.StatusSeeOther, http.StatusFound: http.Redirect(w, r, body, code) default: w.WriteHeader(code) io.WriteString(w, body) } } }
并以这种方式执行:
controller := &web.Controller{} application := &system.Application{} http.HandleFunc("/", application.Route(controller, "Index"))
问题是编译好了。它没有显示任何错误,但是当我转到网站时,仅指向localhost,它显示:
2014/12/27 22:38:16 http: panic serving 127.0.0.1:58304: reflect: Call with too few input arguments goroutine 20 [running]: net/http.func·011() /usr/local/Cellar/go/1.3.3/libexec/src/pkg/net/http/server.go:1100 +0xb7
我找不到任何错误,而且编译还可以,这很奇怪…我是Go语言的新手,所以我不知道发生了什么…
我通过阅读以下内容找到了答案:
http://codingdict.com/questions/63176
因此,与其尝试调用该方法,不如:
methodInterface := finalMethod.Call([]reflect.Value{})[0].Interface() method_route := methodInterface.(func(r *http.Request) (string, int)) body, code := method_route(r)
我只是获得所需的接口,然后将其转换为函数并如此调用它。
methodInterface := finalMethod.Interface() method_route := methodInterface.(func(r *http.Request) (string, int)) body, code := method_route(r)
实际上,这就是我已经在做的事情,但是方式错误。