我有一个看起来像这样的JSON对象。它包含一日三餐，共计21项，因为每餐都是个人入场。
{
"name": "MealPlan 1508620645147",
"items": [
{
"day": 1,
"mealPlanId": 0,
"slot": 1,
"position": 0,
"type": "RECIPE",
"value": "{\"id\":869953,\"imageType\":\"jpg\",\"title\":\"Cream Cheese & Fruit Breakfast Pastries\"}"
},
{
"day": 1,
"mealPlanId": 0,
"slot": 2,
"position": 0,
"type": "RECIPE",
"value": "{\"id\":537176,\"imageType\":\"jpg\",\"title\":\"Leftover Rice Casserole\"}"
},
{
"day": 1,
"mealPlanId": 0,
"slot": 3,
"position": 0,
"type": "RECIPE",
"value": "{\"id\":595927,\"imageType\":\"jpg\",\"title\":\"Spinach and Cheddar Quiche\"}"
},
{
"day": 2,
"mealPlanId": 0,
"slot": 1,
"position": 0,
"type": "RECIPE",
"value": "{\"id\":536716,\"imageType\":\"jpg\",\"title\":\"Candied Pecan Waffles\"}"
},
{
"day": 2,
"mealPlanId": 0,
"slot": 2,
"position": 0,
"type": "RECIPE",
"value": "{\"id\":893265,\"imageType\":\"jpg\",\"title\":\"Tahini Date Smoothie Bowls\"}"
},
{
"day": 2,
"mealPlanId": 0,
"slot": 3,
"position": 0,
"type": "RECIPE",
"value": "{\"id\":512880,\"imageType\":\"jpg\",\"title\":\"Grilled Caprese Salad Sandwich for #SundaySupper\"}"
},
{
"day": 3,
"mealPlanId": 0,
"slot": 1,
"position": 0,
"type": "RECIPE",
"value": "{\"id\":648647,\"imageType\":\"jpg\",\"title\":\"Jumbo Blueberry Muffins\"}"
},
{
"day": 3,
"mealPlanId": 0,
"slot": 2,
"position": 0,
"type": "RECIPE",
"value": "{\"id\":548554,\"imageType\":\"jpg\",\"title\":\"Brie, Pesto, and Sweet Pepper Grilled Cheese\"}"
},
{
"day": 3,
"mealPlanId": 0,
"slot": 3,
"position": 0,
"type": "RECIPE",
"value": "{\"id\":438024,\"imageType\":\"jpg\",\"title\":\"Mother's Manicotti\"}"
},
{
"day": 4,
"mealPlanId": 0,
"slot": 1,
"position": 0,
"type": "RECIPE",
"value": "{\"id\":681594,\"imageType\":\"jpg\",\"title\":\"Huevos Rancheros\"}"
},
{
"day": 4,
"mealPlanId": 0,
"slot": 2,
"position": 0,
"type": "RECIPE",
"value": "{\"id\":99184,\"imageType\":\"jpg\",\"title\":\"Black Bean Tacos\"}"
},
{
"day": 4,
"mealPlanId": 0,
"slot": 3,
"position": 0,
"type": "RECIPE",
"value": "{\"id\":604514,\"imageType\":\"jpg\",\"title\":\"Cheddar Scallion Dutch Baby\"}"
},
{
"day": 5,
"mealPlanId": 0,
"slot": 1,
"position": 0,
"type": "RECIPE",
"value": "{\"id\":622672,\"imageType\":\"jpg\",\"title\":\"Cinnamon-Sugar Streusel Baked French Toast\"}"
},
{
"day": 5,
"mealPlanId": 0,
"slot": 2,
"position": 0,
"type": "RECIPE",
"value": "{\"id\":636178,\"imageType\":\"jpg\",\"title\":\"Broccoli Cheddar Soup, A Panera Bread Co. Copycat\"}"
},
{
"day": 5,
"mealPlanId": 0,
"slot": 3,
"position": 0,
"type": "RECIPE",
"value": "{\"id\":452482,\"imageType\":\"jpg\",\"title\":\"Slow Cooker Macaroni and Cheese I\"}"
},
{
"day": 6,
"mealPlanId": 0,
"slot": 1,
"position": 0,
"type": "RECIPE",
"value": "{\"id\":157272,\"imageType\":\"jpg\",\"title\":\"Pomegranate-Nutella Waffles\"}"
},
{
"day": 6,
"mealPlanId": 0,
"slot": 2,
"position": 0,
"type": "RECIPE",
"value": "{\"id\":619111,\"imageType\":\"jpg\",\"title\":\"Barley, Bulgur and Vegetable Vegan Casserole\"}"
},
{
"day": 6,
"mealPlanId": 0,
"slot": 3,
"position": 0,
"type": "RECIPE",
"value": "{\"id\":510089,\"imageType\":\"jpg\",\"title\":\"Stovetop Mac and Cheese\"}"
},
{
"day": 7,
"mealPlanId": 0,
"slot": 1,
"position": 0,
"type": "RECIPE",
"value": "{\"id\":551869,\"imageType\":\"jpg\",\"title\":\"Berry Smoothie\"}"
},
{
"day": 7,
"mealPlanId": 0,
"slot": 2,
"position": 0,
"type": "RECIPE",
"value": "{\"id\":590452,\"imageType\":\"jpg\",\"title\":\"Cheesy Baked Pasta with Eggplant and Artichokes\"}"
},
{
"day": 7,
"mealPlanId": 0,
"slot": 3,
"position": 0,
"type": "RECIPE",
"value": "{\"id\":590452,\"imageType\":\"jpg\",\"title\":\"Cheesy Baked Pasta with Eggplant and Artichokes\"}"
}
]
}
我想把它解组成一系列结构，每个结构可以作为早餐，午餐，晚餐。所以，我希望我的结构看起来像这样，其中ID是来自JSON的value.id字段，而Name是来自JSON的value.title字段，{{1是Breakfast的项目，午餐是slot:1的项目，slot:2是Dinner的项目。
slot:3我怎样才能在Go中实现这一目标？我最初的想法是创建一个中间type Day struct {
Breakfast meal
Lunch meal
Dinner meal
}
type meal struct {
ID int
Name string
}
来保存来自JSON的所有数据，然后使用我需要的字段创建另一个struct。如何在不使用中间人struct的情况下执行此操作？
答案 0 :(得分：1)
mayo是否建议并实施了UnmarshalJSON
func (wp *WeekPlan) UnmarshalJSON(b []byte) error {
wp.Days = make([]Day, 7)
var f map[string]*json.RawMessage
json.Unmarshal(b, &f)
var v []map[string]interface{}
json.Unmarshal(*f["items"], &v)
for _, item := range v {
day := int(item["day"].(float64)) - 1
mealnumber := int(item["slot"].(float64))
var value map[string]interface{}
json.Unmarshal([]byte(item["value"].(string)), &value)
fmt.Println(value)
id := int(value["id"].(float64))
name := value["title"].(string)
thisMeal := Meal{ID: id, Name: name}
var dateUpdate Day
dateUpdate = wp.Days[day]
switch mealnumber {
case 1:
dateUpdate.Breakfast = thisMeal
case 2:
dateUpdate.Lunch = thisMeal
default:
dateUpdate.Dinner = thisMeal
}
wp.Days[day] = dateUpdate
}
return nil
}
type WeekPlan struct {
Days []Day
}
type Day struct {
Breakfast Meal
Lunch Meal
Dinner Meal
}
type Meal struct {
ID int
Name string
CookTime int
Image string
}