Golang經過反射檢測變量類型

 

What you are wasting today is tomorrow for those who died yesterday; what you hate now is the future you can not go back.

你所浪費的今天是昨天死去的人奢望的明天； 你所厭惡的如今是將來的你回不去的曾經。

簡單的記錄一下吧。

package main

import (
	"reflect"
	"fmt"
	"strings"
)
type Foo struct {
	A int `tag1:"Tag1" tag2:"Second Tag"`
	B string
}
func main(){
	f := Foo{A: 10, B: "Salutations"}
	fPtr := &f
	m := map[string]int{"A": 1 , "B":2}
	ch := make(chan int)
	sl:= []int{1,32,34}
	str := "string var"
	strPtr := &str

	tMap := examiner(reflect.TypeOf(f), 0)
	tMapPtr := examiner(reflect.TypeOf(fPtr), 0)
	tMapM := examiner(reflect.TypeOf(m), 0)
	tMapCh := examiner(reflect.TypeOf(ch), 0)
	tMapSl := examiner(reflect.TypeOf(sl), 0)
	tMapStr := examiner(reflect.TypeOf(str), 0)
	tMapStrPtr := examiner(reflect.TypeOf(strPtr), 0)

	fmt.Println("tMap :", tMap)
	fmt.Println("tMapPtr: ",tMapPtr)
	fmt.Println("tMapM: ",tMapM)
	fmt.Println("tMapCh: ",tMapCh)
	fmt.Println("tMapSl: ",tMapSl)
	fmt.Println("tMapStr: ",tMapStr)
	fmt.Println("tMapStrPtr: ",tMapStrPtr)
}

func examiner(t reflect.Type, depth int) map[int]map[string]string{
	outType := make(map[int]map[string]string)
	outType = map[int] map[string]string{depth:{"Name":t.Name(), "Kind":t.Kind().String()}}
  
    // 若是須要繼續檢測元素的類型
	switch t.Kind() {
	case reflect.Array, reflect.Chan, reflect.Map, reflect.Ptr, reflect.Slice:
		outType = make(map[int]map[string]string)
		tMap := examiner(t.Elem(), depth)
		for k, v := range tMap{
			outType[k] = v
		}

	case reflect.Struct:
		outType = make(map[int]map[string]string)
		for i := 0; i < t.NumField(); i++ {
			f := t.Field(i)
			outType[i] = map[string]string{
				"Name":f.Name,
				"Kind":f.Type.String(),
			}
		}
	}

	return outType
}