随笔分类 -  Linq

c# 生成树方法
摘要：数据结构接口： /// <summary> /// 实体类必须实现接口 /// </summary> public interface IToTreeModel { int Id { get; set; } int ParentId { get; set; } List<IToTreeModel> 阅读全文
posted @ 2020-11-05 18:27 芮源 阅读(639) 评论(0) 推荐(0)
c# 集合的合并举例
摘要：eg： List<string> listA = new List<string> {"1","2","3"}; List<string> listB = new List<string> {"2","4","17"}; List<string> Result = listA.Union(listB 阅读全文
posted @ 2019-12-02 10:47 芮源 阅读(932) 评论(0) 推荐(0)
sql SqlBulkCopy SqlDataAdapter 数据处理
摘要：public class sqlclass { //复制大量数据 public static void BulkToDB(DataTable dt, string TableName) { SqlConnection sqlConn = new SqlConnection(Configuration 阅读全文
posted @ 2019-09-18 16:33 芮源
c# linq List<T> To Excel
摘要：StringBuilder str = new StringBuilder(); str.Append(DateTime.Now.Millisecond); string url = "/Content/" + str + ".xlsx"; var path = Server.MapPath(url 阅读全文
posted @ 2019-09-18 15:05 芮源
c# 异步请求demo
摘要：public static async Task<List<Syncchip>> DownSyncchipList(int id) { using (var client = new HttpClient()) { try { string url = ApiServer.url+"/school/ 阅读全文
posted @ 2019-09-02 11:39 芮源
DataTable到Access
摘要：conn.Open(); OleDbDataAdapter Bada = new OleDbDataAdapter("select * from " + cmdText, conn);//建立一个DataAdapter对象 OleDbCommandBuilder cb = new OleDbComm 阅读全文
posted @ 2019-08-26 08:55 芮源 阅读(735) 评论(0) 推荐(0)
linq表连接
摘要：SELECT ( SELECT d.DeptName FROM Dept d WHERE d.Id=p.DeptId ) DeptName, count( p.DeptId) AS Count FROM Person pGROUP BY p.DeptIdvar dept = (from p in d 阅读全文
posted @ 2019-07-23 08:39 芮源