如何实现连接数据库和简单的操作
下面一段代码演示的最简单的一种数据库连接方法和对其的简单操作:
string sConnection = @"server=(local)\SQLEXPRESS;database=Forum;Trusted_Connection=True";//连接数据源
using (SqlConnection conn = new SqlConnection(sConnection))
{
conn.Open();
using (SqlCommand comd = new SqlCommand())//实例化数据库操作对象
{
comd.Connection = conn;
comd.CommandText = "Insert into tbClass(ClassName) values('网页设计')";//向数据库中插入‘网页设计’
Response.Write(string.Format("在tbClass中插入了{0}条记录<br>", comd.ExecuteNonQuery()));
comd.CommandText = "Select ClassID from tbClass where ClassName='网页设计'";
string sClassID = comd.ExecuteScalar().ToString();
Response.Write(string.Format("ClassID为{0}<br>", sClassID));
comd.CommandText = string.Format("Insert into tbBoard(BoardName,BoardClassID) values ('PHOTOSHOP','{0}');Insert into tbBoard(BoardName,BoardClassID) values ('FIREWORKS','{0}')", sClassID);
Response.Write(string.Format("在tbBoard中插入了{0}条记录<br>", comd.ExecuteNonQuery()));
comd.CommandText = "Update tbBoard set BoardName='PS技术' where BoardName='PHOTOSHOP'";
Response .Write (string .Format ("在tbBoard中修改了{0}条记录<br>",comd .ExecuteNonQuery ()));
comd .CommandText =string .Format ("Delete from tbBoard where BoardClassID='{0}'",sClassID );
Response.Write(string .Format ("在tbBoard中删除了{0}条记录<br>", comd.ExecuteNonQuery()));
comd.CommandText = string.Format("Delete from tbClass where ClassID='{0}'", sClassID);
Response .Write (string .Format ("在tbClass中删除了{0}条记录<br>",comd .ExecuteNonQuery ()));
}
}
}
using (SqlConnection conn = new SqlConnection(sConnection))
{
conn.Open();
using (SqlCommand comd = new SqlCommand())//实例化数据库操作对象
{
comd.Connection = conn;
comd.CommandText = "Insert into tbClass(ClassName) values('网页设计')";//向数据库中插入‘网页设计’
Response.Write(string.Format("在tbClass中插入了{0}条记录<br>", comd.ExecuteNonQuery()));
comd.CommandText = "Select ClassID from tbClass where ClassName='网页设计'";
string sClassID = comd.ExecuteScalar().ToString();
Response.Write(string.Format("ClassID为{0}<br>", sClassID));
comd.CommandText = string.Format("Insert into tbBoard(BoardName,BoardClassID) values ('PHOTOSHOP','{0}');Insert into tbBoard(BoardName,BoardClassID) values ('FIREWORKS','{0}')", sClassID);
Response.Write(string.Format("在tbBoard中插入了{0}条记录<br>", comd.ExecuteNonQuery()));
comd.CommandText = "Update tbBoard set BoardName='PS技术' where BoardName='PHOTOSHOP'";
Response .Write (string .Format ("在tbBoard中修改了{0}条记录<br>",comd .ExecuteNonQuery ()));
comd .CommandText =string .Format ("Delete from tbBoard where BoardClassID='{0}'",sClassID );
Response.Write(string .Format ("在tbBoard中删除了{0}条记录<br>", comd.ExecuteNonQuery()));
comd.CommandText = string.Format("Delete from tbClass where ClassID='{0}'", sClassID);
Response .Write (string .Format ("在tbClass中删除了{0}条记录<br>",comd .ExecuteNonQuery ()));
}
}
}
这段代码能够实现简单的对数据库的增、删、改等操作。