added get page

rspagination/rspagination.go

@@ -38,3 +38,24 @@ func DbPageQuery(database *gorm.DB, query PageQuery, paginationLimit int, result
 		Order(orderBy).
 		Find(result)
 }
+
+// GetPage returns start and end for pagination
+// can be used like this: robots[start:end]
+func GetPage(lenList int, page int, limit int) (start int, end int) {
+	if page <= 0 {
+		page = 1
+	}
+
+	start = (page - 1) * limit
+	end = page * limit
+
+	if start > lenList {
+		start = lenList
+	}
+
+	if end > lenList {
+		end = lenList
+	}
+
+	return start, end
+}