SqlServer使用公用表表达式（CTE）实现无限级树形构建_MsSql_

 DECLARE @Level INT=3 ;WITH cte_parent(CategoryID,CategoryName,ParentCategoryID,Level) AS ( SELECT category_id,category_name,parent_category_id,1 AS Level FROM TianShenLogistic.dbo.ProductCategory WITH(NOLOCK) WHERE category_id IN ( SELECT category_id FROM TianShenLogistic.dbo.ProductCategory WHERE parent_category_id=0 ) UNION ALL SELECT b.category_id,b.category_name,b.parent_category_id,a.Level+1 AS Level FROM TianShenLogistic.dbo.ProductCategory b INNER JOIN cte_parent a ON a.CategoryID = b.parent_category_id ) SELECT CategoryID AS value, CategoryName as label, ParentCategoryID As parentId, Level FROM cte_parent WHERE Level <=@Level; public static List GetLogisticsCategoryByParent(int? level) { if (level < 1) return null; var dataResult = CategoryDA.GetLogisticsCategoryByParent(level); var firstlevel = dataResult.Where(d => d.level == 1).ToList(); BuildCategory(dataResult, firstlevel); return firstlevel; } private static void BuildCategory(List allCategoryList, List categoryList) { foreach (var category in categoryList) { var subCategoryList = allCategoryList.Where(c => c.parentId == category.value).ToList(); if (subCategoryList.Count > 0) { if (category.children == null) category.children = new List(); category.children.AddRange(subCategoryList); BuildCategory(allCategoryList, category.children); } } }