如何将SQL参数与NpgsqlDataAdapter一起使用?
是否可以像使用NpgsqlDataAdapter一样,将参数与NpgsqlDataAdapter一起使用:如何将SQL参数与NpgsqlDataAdapter一起使用?,sql,parameters,npgsql,Sql,Parameters,Npgsql,是否可以像使用NpgsqlDataAdapter一样,将参数与NpgsqlDataAdapter一起使用: string sql = "SELECT * FROM tbl_student WHERE name = @val"; NpgsqlCommand command = new NpgsqlCommand(sql, conn); command.Parameters.AddWithValue("@val", name); 我有一
string sql = "SELECT * FROM tbl_student WHERE name = @val";
NpgsqlCommand command = new NpgsqlCommand(sql, conn);
command.Parameters.AddWithValue("@val", name);
我有一段代码,它显示了我在gridview中看到的学生的信息:
string sql = "SELECT * FROM tbl_student WHERE studentname = '" + name + "'";
DataSet ds = new DataSet();
DataTable dt = new DataTable();
NpgsqlDataAdapter da = new NpgsqlDataAdapter(sql, conn);
ds.Reset();
da.Fill(ds); // filling DataSet with result from NpgsqlDataAdapter
dt = ds.Tables[0]; // select select first column
GridView1.DataSource = dt; //connect grid to DataTable
GridView1.DataBind();
我的问题是:我能否以某种方式使用参数(如上面的示例)而不是在SQL中使用“+name+”?
我已经学会了如何使用参数,在使用NpgsqlDataAdapter时是否也需要参数
谢谢。我以前也有同样的问题,我就是这么想的:
string sql = "SELECT * FROM tbl_student WHERE studentname = @param";
NpgsqlCommand command = new NpgsqlCommand(sql,conn);
command.Parameters.Add("@param", textBox_studentname.Text); //add the parameter into the sql command
DataTable dt = new DataTable();
//load the DataReader object of the command to the DataTable
dt.Load(NpgsqlDataReader reader = command.ExecuteReader(CommandBehavior.CloseConnection));
GridView1.DataSource = dt;
你可以阅读和阅读。我以前也有同样的问题,这就是我想到的:
string sql = "SELECT * FROM tbl_student WHERE studentname = @param";
NpgsqlCommand command = new NpgsqlCommand(sql,conn);
command.Parameters.Add("@param", textBox_studentname.Text); //add the parameter into the sql command
DataTable dt = new DataTable();
//load the DataReader object of the command to the DataTable
dt.Load(NpgsqlDataReader reader = command.ExecuteReader(CommandBehavior.CloseConnection));
GridView1.DataSource = dt;
你可以阅读和阅读。我以前也有同样的问题,这就是我想到的:
string sql = "SELECT * FROM tbl_student WHERE studentname = @param";
NpgsqlCommand command = new NpgsqlCommand(sql,conn);
command.Parameters.Add("@param", textBox_studentname.Text); //add the parameter into the sql command
DataTable dt = new DataTable();
//load the DataReader object of the command to the DataTable
dt.Load(NpgsqlDataReader reader = command.ExecuteReader(CommandBehavior.CloseConnection));
GridView1.DataSource = dt;
你可以阅读和阅读。我以前也有同样的问题,这就是我想到的:
string sql = "SELECT * FROM tbl_student WHERE studentname = @param";
NpgsqlCommand command = new NpgsqlCommand(sql,conn);
command.Parameters.Add("@param", textBox_studentname.Text); //add the parameter into the sql command
DataTable dt = new DataTable();
//load the DataReader object of the command to the DataTable
dt.Load(NpgsqlDataReader reader = command.ExecuteReader(CommandBehavior.CloseConnection));
GridView1.DataSource = dt;
你可以阅读和阅读