c# - SqlCeCommand 异常

Question

我有这个代码：

SqlCeConnection connection = new SqlCeConnection(conString);
connection.Open();
connection.CreateCommand();
cmd.CommandText = "CREATE TABLE Settings (id int IDENTITY PRIMARY KEY, host nvarchar(50), port int, rk_host nvarchar(50), rk_port int, stationcode int, guesttypecode int)";
cmd.ExecuteNonQuery();
cmd = connection.CreateCommand();
cmd.CommandText = "INSERT INTO Settings ([host], [port], [rk_host], [rk_port], [stationcode], [guesttypecode]) VALUES ('" + Settings.host + "', '" + Settings.rk_host + "', '" + Settings.rk_port + "', '" + Settings.port + "', '" + Settings.stationcode + "', '" + Settings.guesttypecode + "')";
cmd.ExecuteNonQuery();
connection.Close();

在第二个ExecuteNonQuery我有一个例外："Data conversion failed. [ OLE DB status value (if known) = 2 ]"

有谁能够帮助我？

Answer 1

在 Int 类型列上，您应该从查询中删除单引号

cmd.CommandText = "INSERT INTO Settings ([host], [port], [rk_host], [rk_port], [stationcode], [guesttypecode]) VALUES ('" + Settings.host + "', '" + Settings.rk_host + "', " + Settings.rk_port + ", '" + Settings.port + "', " + Settings.stationcode + ", " + Settings.guesttypecode + ")";

Answer 2

第一个建议是永远不要这样写你的查询，因为这会导致SQL Injection。其次，您正在阅读您的设置并将它们插入您的表格而不考虑它们的类型。您需要进行类型转换（例如int.Parse(Settings.port)