访问京东API，获取结账必要信息。

business/util/Contain.go

@@ -1,25 +0,0 @@
-package util
-
-import (
-	"errors"
-	"reflect"
-)
-
-// 判断obj是否在target中，target支持的类型arrary,slice,map
-func Contain(obj interface{}, target interface{}) (bool, error) {
-	targetValue := reflect.ValueOf(target)
-	switch reflect.TypeOf(target).Kind() {
-	case reflect.Slice, reflect.Array:
-		for i := 0; i < targetValue.Len(); i++ {
-			if targetValue.Index(i).Interface() == obj {
-				return true, nil
-			}
-		}
-	case reflect.Map:
-		if targetValue.MapIndex(reflect.ValueOf(obj)).IsValid() {
-			return true, nil
-		}
-	}
-
-	return false, errors.New("not in array")
-}