53 lines
1.3 KiB
Go
53 lines
1.3 KiB
Go
package utils
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import (
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"gorm.io/gorm"
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)
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// 标准分页结构体，接收最原始的DO
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// 建议在外部再建一个字段一样的结构体，用以将DO转换成DTO或VO
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type Page[T any] struct {
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CurrentPage int64 `json:"currentPage"`
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PageSize int64 `json:"pageSize"`
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Total int64 `json:"total"`
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Pages int64 `json:"pages"`
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Data []T `json:"data"`
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}
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// 各种查询条件先在query设置好后再放进来
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func (page *Page[T]) SelectPages(query *gorm.DB) (e error) {
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var model T
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query.Model(&model).Count(&page.Total)
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if page.Total == 0 {
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page.Data = []T{}
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return
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}
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e = query.Model(&model).Scopes(Paginate(page)).Find(&page.Data).Error
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return
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}
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func Paginate[T any](page *Page[T]) func(db *gorm.DB) *gorm.DB {
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return func(db *gorm.DB) *gorm.DB {
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if page.CurrentPage <= 0 {
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page.CurrentPage = 1
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}
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switch {
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case page.PageSize > 10000:
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page.PageSize = 10000 // 限制一下分页大小
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case page.PageSize <= 0:
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page.PageSize = 10
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}
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page.Pages = page.Total / page.PageSize
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if page.Total%page.PageSize != 0 {
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page.Pages++
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}
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p := page.CurrentPage
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if page.CurrentPage > page.Pages {
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p = page.Pages
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}
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size := page.PageSize
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offset := int((p - 1) * size)
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return db.Offset(offset).Limit(int(size))
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}
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}
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