OracleConnection conn = new OracleConnection(ConnectionString);
string str = "select * from table1 where name like '%:name%'";
OracleCommand cmd = new OracleCommand(str, conn);
OracleParameter name = new OracleParameter(":name", OracleType.Char, 50);
name.Value = TextBox1.Text;    
cmd.Parameters.Add(name);
conn.Open();
OracleDataReader dr = cmd.ExecuteReader();//到这里出错

"select * from table1 where name like N'%'+:name+'%'";

------解决方案--------------------
% 
业务逻辑层把:name值得百分号给加上试试，然后把引号去掉