C# update问题！！！！！

SqlConnection strcon = new SqlConnection(System.Configuration.ConfigurationManager.AppSettings["strcon"]);
strcon.Open();
OrderTime1.Text = DateTime.Now.ToString();
SqlCommand scd = new SqlCommand("insert into tb_NReckoning (NoticeId,DepotName,DepotDress,StockDate,CommodityName,CommodityWeight,CommoditySize,MangmanName)values('" + NoticeId + "','" + DepotId + "','" + changkud + "','" + OrderTime1.Text + "','" + commodityN + "','" + commodityW + "','" + commodityS + "','" + ManageMan + "')", strcon);
scd.ExecuteNonQuery();
strcon.Close();
SqlConnection strcon1 = new SqlConnection(System.Configuration.ConfigurationManager.AppSettings["strcon"]);
** SqlCommand scd1 = new SqlCommand("UPDATE tb_Depot SET DepotSizeS='DepotIdss', strcon1");
scd1.ExecuteNonQuery();
strcon1.Close();
Response.Write("alert('货物成功入库');location='Stock_add.aspx'");**
为什么会出现Connection没有初始化

应该是
SqlConnection strcon = new SqlConnection(System.Configuration.ConfigurationManager.AppSettings["strcon"]);

这个地方有问题了，未初始化成功，检查一下你的配置

配置文件里有 strcon这个吗