英文:
The function returns nil
问题
我是一个初学者，我编写了一个函数，用于检查请求中的pagination.Main == true，如果是，则函数返回prod，否则返回prod_2。默认参数是main == true，但如果我将其更改为false，我会得到"data": null。
我的函数：
func GetAllIproducts(q *models.Products, g *models.Products_2, pagination *models.Params) (*[]models.Products, *[]models.Products_2) {var prod []models.Productsvar prod_2 []models.Products_2offset := (pagination.Page - 1) * pagination.Limitif pagination.Main {if pagination.Cat_id == nil {config.DB.Model(&models.Products{}).Where(q).Limit(pagination.Limit).Offset(offset).Find(&prod)} else {config.DB.Model(&models.Products{}).Where(q).Where("cat_id IN (?)", pagination.Cat_id).Limit(pagination.Limit).Offset(offset).Find(&prod)}return &prod, nil} else {if pagination.Cat_id == nil {config.DB.Model(&models.Products_2{}).Where(g).Limit(pagination.Limit).Offset(offset).Find(&prod_2)} else {config.DB.Model(&models.Products_2{}).Where(g).Where("cat_id IN (?)", pagination.Cat_id).Limit(pagination.Limit).Offset(offset).Find(&prod_2)}return nil, &prod_2}}
func GetAllProducts_by_multi_params(c *gin.Context) {pagination := GenerateMultiParams(c)var prod models.Productsvar prod_2 models.Products_2ProdLists, _ := GetAllIproducts(&prod, &prod_2, &pagination)c.JSON(http.StatusOK, gin.H{"data": ProdLists,})}
英文:
I'm a beginner, I wrote a function that checks if in the request pagination.Main == true , then the function returns prod, otherwise prod_2. The default parameter is main == true , but if I change it to false I get "data": null
My funcs:
func GetAllIproducts(q *models.Products, g *models.Products_2, pagination *models.Params) (*[]models.Products, *[]models.Products_2) {var prod []models.Productsvar prod_2 []models.Products_2offset := (pagination.Page - 1) * pagination.Limitif pagination.Main {if pagination.Cat_id == nil {config.DB.Model(&models.Products{}).Where(q).Limit(pagination.Limit).Offset(offset).Find(&prod)} else {config.DB.Model(&models.Products{}).Where(q).Where("cat_id IN (?)", pagination.Cat_id).Limit(pagination.Limit).Offset(offset).Find(&prod)}return &prod, nil} else {if pagination.Cat_id == nil {config.DB.Model(&models.Products_2{}).Where(g).Limit(pagination.Limit).Offset(offset).Find(&prod_2)} else {config.DB.Model(&models.Products_2{}).Where(g).Where("cat_id IN (?)", pagination.Cat_id).Limit(pagination.Limit).Offset(offset).Find(&prod_2)}return nil, &prod_2}}
func GetAllProducts_by_multi_params(c *gin.Context) {pagination := GenerateMultiParams(c)var prod models.Productsvar prod_2 models.Products_2ProdLists, _ := GetAllIproducts(&prod, &prod_2, &pagination)c.JSON(http.StatusOK, gin.H{"data": ProdLists,})}
答案1
得分: 0
第二个返回值由下划线 _ 保存在 ProdLists 中
ProdLists, _ := GetAllIproducts(&prod, &prod_2, &pagination)
你可以将其更改为 Prod2Lists 并检查是否为 nil，例如：
ProdLists, Prod2Lists := GetAllIproducts(&prod, &prod_2, &pagination)如果 ProdLists 不为 nil {c.JSON(http.StatusOK, gin.H{"data": ProdLists,})} else {c.JSON(http.StatusOK, gin.H{"data": Prod2Lists,})}
英文:
The second return value is hold by the underscore _ in
ProdLists, _ := GetAllIproducts(&prod, &prod_2, &pagination)
You can change it to Prod2Lists and check for nil, like:
ProdLists, Prod2Lists := GetAllIproducts(&prod, &prod_2, &pagination)If ProdLists != nil {c.JSON(http.StatusOK, gin.H{"data": ProdLists,})} else {c.JSON(http.StatusOK, gin.H{"data": Prod2Lists,})}
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