题目我也不知道怎么说的C# WINFORM连接数据库问题

[accome]

string strconnection = ConfigurationManager.AppSettings["strconnec"];
SqlConnection objconnection = new SqlConnection(strconnection);
string sele = "select * from useclassroominf where cclassroomid=" +textBox1.Text.ToString();
SqlCommand objcommand = new SqlCommand(sele, objconnection);
SqlDataReader sr;

objconnection.Open();
sr = objcommand.ExecuteReader();
if (sr.Read())
{

label1.Text = sr.GetString(0) + sr.GetString(1) + sr.GetString(2) + sr.GetString(3) + sr.GetString(4);
}
objconnection.Close();

以上代码报错，我定义的cclassroomid为varchar(50)，数据为汉字，当textbox1输入相同汉字时报错，说列名无效，我猜是因为textBox1.Text.ToString()这个不对，但是不知道怎么改正，请教大大们········

[accome]

。。。。不能沉下。继续等。

[cppfaq]

string sele = "select * from useclassroominf where cclassroomid=N'" + textBox1.Text + "'"; 

[accome]

谢谢了。。。。。。。