数组分页

// 数组分页
func PageData(xs interface{}, page, item int) (interface{}, int) {
    fv := reflect.ValueOf(xs)
    if page == 0 { //第0页返回所有
        return xs, fv.Len()
    }
    data := []interface{}{}
    for i := Skip(page, item); i < fv.Len() && i < Skip(page, item) + item; i++ {
        data = append(data, fv.Index(i).Interface())
    }
    return data, fv.Len()
}

func Skip(page int, item int) int {
    if page == 0 {
        panic("page must gt 0")
    }
    return (page - 1) * item
}

// 数组分页
func GetPageIndex(size, page, item int) (startIdx, endIdx int) {
    if page == 0 { //第0页返回所有
        startIdx = 0
        endIdx = size
    } else {
        startIdx = func() int {
            if size < (page - 1) * item {
                return size
            }
            return (page - 1) * item
        }()
        endIdx = func() int {
            if size < (page - 1) * item + item {
                return size
            }
            return (page - 1) * item + item
        }()
    }
    return
}